diff --git a/xpcom/base/AvailableMemoryTracker.cpp b/xpcom/base/AvailableMemoryTracker.cpp
index b1985db99c4a..874a8e497a1f 100644
--- a/xpcom/base/AvailableMemoryTracker.cpp
+++ b/xpcom/base/AvailableMemoryTracker.cpp
@@ -1,5 +1,5 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim:set ts=2 sw=2 sts=2 ci et: */
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
@@ -325,47 +325,14 @@ CreateDIBSectionHook(HDC aDC,
   return result;
 }
 
-class NumLowMemoryEventsReporter : public nsIMemoryReporter
-{
-  NS_IMETHOD GetProcess(nsACString &aProcess)
-  {
-    aProcess.Truncate();
-    return NS_OK;
-  }
-
-  NS_IMETHOD GetKind(int *aKind)
-  {
-    *aKind = KIND_OTHER;
-    return NS_OK;
-  }
-
-  NS_IMETHOD GetUnits(int *aUnits)
-  {
-    *aUnits = UNITS_COUNT_CUMULATIVE;
-    return NS_OK;
-  }
-};
-
-class NumLowVirtualMemoryEventsMemoryReporter MOZ_FINAL : public NumLowMemoryEventsReporter
+class LowMemoryEventsVirtualReporter MOZ_FINAL : public MemoryReporterBase
 {
 public:
-  NS_DECL_ISUPPORTS
-
-  NS_IMETHOD GetPath(nsACString &aPath)
-  {
-    aPath.AssignLiteral("low-memory-events/virtual");
-    return NS_OK;
-  }
-
-  NS_IMETHOD GetAmount(int64_t *aAmount)
-  {
-    // This memory reporter shouldn't be installed on 64-bit machines, since we
-    // force-disable virtual-memory tracking there.
-    MOZ_ASSERT(sizeof(void*) == 4);
-
-    *aAmount = sNumLowVirtualMemEvents;
-    return NS_OK;
-  }
+  // The description is "???" because we implement GetDescription().
+  LowMemoryEventsVirtualReporter()
+    : MemoryReporterBase("low-memory-events/virtual",
+                         KIND_OTHER, UNITS_COUNT_CUMULATIVE, "???")
+  {}
 
   NS_IMETHOD GetDescription(nsACString &aDescription)
   {
@@ -388,26 +355,26 @@ public:
     }
     return NS_OK;
   }
+
+private:
+  int64_t Amount() MOZ_OVERRIDE
+  {
+    // This memory reporter shouldn't be installed on 64-bit machines, since we
+    // force-disable virtual-memory tracking there.
+    MOZ_ASSERT(sizeof(void*) == 4);
+
+    return sNumLowVirtualMemEvents;
+  }
 };
 
-NS_IMPL_ISUPPORTS1(NumLowVirtualMemoryEventsMemoryReporter, nsIMemoryReporter)
-
-class NumLowCommitSpaceEventsMemoryReporter MOZ_FINAL : public NumLowMemoryEventsReporter
+class LowCommitSpaceEventsReporter MOZ_FINAL : public MemoryReporterBase
 {
 public:
-  NS_DECL_ISUPPORTS
-
-  NS_IMETHOD GetPath(nsACString &aPath)
-  {
-    aPath.AssignLiteral("low-commit-space-events");
-    return NS_OK;
-  }
-
-  NS_IMETHOD GetAmount(int64_t *aAmount)
-  {
-    *aAmount = sNumLowCommitSpaceEvents;
-    return NS_OK;
-  }
+  // The description is "???" because we implement GetDescription().
+  LowCommitSpaceEventsReporter()
+    : MemoryReporterBase("low-commit-space-events",
+                         KIND_OTHER, UNITS_COUNT_CUMULATIVE, "???")
+  {}
 
   NS_IMETHOD GetDescription(nsACString &aDescription)
   {
@@ -430,26 +397,19 @@ public:
     }
     return NS_OK;
   }
+
+private:
+  int64_t Amount() MOZ_OVERRIDE { return sNumLowCommitSpaceEvents; }
 };
 
-NS_IMPL_ISUPPORTS1(NumLowCommitSpaceEventsMemoryReporter, nsIMemoryReporter)
-
-class NumLowPhysicalMemoryEventsMemoryReporter MOZ_FINAL : public NumLowMemoryEventsReporter
+class LowMemoryEventsPhysicalReporter MOZ_FINAL : public MemoryReporterBase
 {
 public:
-  NS_DECL_ISUPPORTS
-
-  NS_IMETHOD GetPath(nsACString &aPath)
-  {
-    aPath.AssignLiteral("low-memory-events/physical");
-    return NS_OK;
-  }
-
-  NS_IMETHOD GetAmount(int64_t *aAmount)
-  {
-    *aAmount = sNumLowPhysicalMemEvents;
-    return NS_OK;
-  }
+  // The description is "???" because we implement GetDescription().
+  LowMemoryEventsPhysicalReporter()
+    : MemoryReporterBase("low-memory-events/physical",
+                         KIND_OTHER, UNITS_COUNT_CUMULATIVE, "???")
+  {}
 
   NS_IMETHOD GetDescription(nsACString &aDescription)
   {
@@ -473,9 +433,10 @@ public:
     }
     return NS_OK;
   }
-};
 
-NS_IMPL_ISUPPORTS1(NumLowPhysicalMemoryEventsMemoryReporter, nsIMemoryReporter)
+private:
+  int64_t Amount() MOZ_OVERRIDE { return sNumLowPhysicalMemEvents; }
+};
 
 #endif // defined(XP_WIN)
 
@@ -592,10 +553,10 @@ void Activate()
   Preferences::AddUintVarCache(&sLowMemoryNotificationIntervalMS,
       "memory.low_memory_notification_interval_ms", 10000);
 
-  NS_RegisterMemoryReporter(new NumLowCommitSpaceEventsMemoryReporter());
-  NS_RegisterMemoryReporter(new NumLowPhysicalMemoryEventsMemoryReporter());
+  NS_RegisterMemoryReporter(new LowCommitSpaceEventsReporter());
+  NS_RegisterMemoryReporter(new LowMemoryEventsPhysicalReporter());
   if (sizeof(void*) == 4) {
-    NS_RegisterMemoryReporter(new NumLowVirtualMemoryEventsMemoryReporter());
+    NS_RegisterMemoryReporter(new LowMemoryEventsVirtualReporter());
   }
   sHooksActive = true;
 #endif
diff --git a/xpcom/base/MapsMemoryReporter.cpp b/xpcom/base/MapsMemoryReporter.cpp
index 757e2582fe9d..09fd1354a423 100644
--- a/xpcom/base/MapsMemoryReporter.cpp
+++ b/xpcom/base/MapsMemoryReporter.cpp
@@ -1,5 +1,5 @@
-/* -*- Mode: C++; tab-width: 50; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim:set ts=2 sw=2 sts=2 ci et: */
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
@@ -520,8 +520,20 @@ MapsReporter::ParseMapBody(
   return NS_OK;
 }
 
-static nsresult GetUSS(int64_t *n)
+class ResidentUniqueReporter MOZ_FINAL : public MemoryReporterBase
 {
+public:
+  ResidentUniqueReporter()
+    : MemoryReporterBase("resident-unique", KIND_OTHER, UNITS_BYTES,
+"Memory mapped by the process that is present in physical memory and not "
+"shared with any other processes.  This is also known as the process's unique "
+"set size (USS).  This is the amount of RAM we'd expect to be freed if we "
+"closed this process.")
+  {}
+
+private:
+  NS_IMETHOD GetAmount(int64_t *aAmount)
+  {
     // You might be tempted to calculate USS by subtracting the "shared" value
     // from the "resident" value in /proc/<pid>/statm.  But at least on Linux,
     // statm's "shared" value actually counts pages backed by files, which has
@@ -533,42 +545,33 @@ static nsresult GetUSS(int64_t *n)
     // smaps reporter in normal about:memory operation).  Hopefully this
     // implementation is fast enough not to matter.
 
-    *n = 0;
+    *aAmount = 0;
 
     FILE *f = fopen("/proc/self/smaps", "r");
     NS_ENSURE_STATE(f);
 
     int64_t total = 0;
     char line[256];
-    while(fgets(line, sizeof(line), f)) {
-        long long val = 0;
-        if(sscanf(line, "Private_Dirty: %lld kB", &val) == 1 ||
-           sscanf(line, "Private_Clean: %lld kB", &val) == 1) {
-            total += val * 1024; // convert from kB to bytes
-        }
+    while (fgets(line, sizeof(line), f)) {
+      long long val = 0;
+      if (sscanf(line, "Private_Dirty: %lld kB", &val) == 1 ||
+          sscanf(line, "Private_Clean: %lld kB", &val) == 1) {
+        total += val * 1024; // convert from kB to bytes
+      }
     }
-    *n = total;
+    *aAmount = total;
 
     fclose(f);
     return NS_OK;
-}
-
-NS_FALLIBLE_MEMORY_REPORTER_IMPLEMENT(USS,
-    "resident-unique",
-    KIND_OTHER,
-    UNITS_BYTES,
-    GetUSS,
-    "Memory mapped by the process that is present in physical memory and not "
-    "shared with any other processes.  This is also known as the process's "
-    "unique set size (USS).  This is the amount of RAM we'd expect to be freed "
-    "if we closed this process.")
+  }
+};
 
 void Init()
 {
   nsCOMPtr<nsIMemoryMultiReporter> reporter = new MapsReporter();
   NS_RegisterMemoryMultiReporter(reporter);
 
-  NS_RegisterMemoryReporter(new NS_MEMORY_REPORTER_NAME(USS));
+  NS_RegisterMemoryReporter(new ResidentUniqueReporter());
 }
 
 } // namespace MapsMemoryReporter
diff --git a/xpcom/base/nsMemoryInfoDumper.cpp b/xpcom/base/nsMemoryInfoDumper.cpp
index 728edf18aff9..d6716918ecbd 100644
--- a/xpcom/base/nsMemoryInfoDumper.cpp
+++ b/xpcom/base/nsMemoryInfoDumper.cpp
@@ -16,6 +16,7 @@
 #include "mozilla/dom/ContentChild.h"
 #include "nsIConsoleService.h"
 #include "nsICycleCollectorListener.h"
+#include "nsIMemoryReporter.h"
 #include "nsDirectoryServiceDefs.h"
 #include "nsGZFileWriter.h"
 #include "nsJSEnvironment.h"
diff --git a/xpcom/base/nsMemoryReporterManager.cpp b/xpcom/base/nsMemoryReporterManager.cpp
index 3b35fa6fce75..b1b0d407db59 100644
--- a/xpcom/base/nsMemoryReporterManager.cpp
+++ b/xpcom/base/nsMemoryReporterManager.cpp
@@ -490,7 +490,7 @@ public:
 "exact amount requested is not recorded.)")
     {}
 private:
-    int64_t Amount()
+    int64_t Amount() MOZ_OVERRIDE
     {
         jemalloc_stats_t stats;
         jemalloc_stats(&stats);
diff --git a/xpcom/build/XPCOM.h b/xpcom/build/XPCOM.h
index 5afca04ff203..44c5059e164d 100644
--- a/xpcom/build/XPCOM.h
+++ b/xpcom/build/XPCOM.h
@@ -82,7 +82,6 @@
 #include "nsIInterfaceRequestor.h"
 #include "nsILineInputStream.h"
 #include "nsIMemory.h"
-#include "nsIMemoryReporter.h"
 #include "nsIMutable.h"
 #include "nsIObserver.h"
 #include "nsIObserverService.h"
diff --git a/xpcom/components/nsCategoryManager.cpp b/xpcom/components/nsCategoryManager.cpp
index 4d853604090a..7765add9feab 100644
--- a/xpcom/components/nsCategoryManager.cpp
+++ b/xpcom/components/nsCategoryManager.cpp
@@ -402,14 +402,20 @@ CategoryEnumerator::enumfunc_createenumerator(const char* aStr, CategoryNode* aN
 
 NS_IMPL_QUERY_INTERFACE1(nsCategoryManager, nsICategoryManager)
 
-NS_MEMORY_REPORTER_MALLOC_SIZEOF_FUN(CategoryManagerMallocSizeOf)
-
-NS_MEMORY_REPORTER_IMPLEMENT(CategoryManager,
-    "explicit/xpcom/category-manager",
-    KIND_HEAP,
-    nsIMemoryReporter::UNITS_BYTES,
-    nsCategoryManager::GetCategoryManagerSize,
-    "Memory used for the XPCOM category manager.")
+class XPCOMCategoryManagerReporter MOZ_FINAL : public MemoryReporterBase
+{
+public:
+    XPCOMCategoryManagerReporter()
+      : MemoryReporterBase("explicit/xpcom/category-manager",
+                           KIND_HEAP, UNITS_BYTES,
+                           "Memory used for the XPCOM category manager.")
+    {}
+private:
+    int64_t Amount() MOZ_OVERRIDE
+    {
+        return nsCategoryManager::SizeOfIncludingThis(MallocSizeOf);
+    }
+};
 
 NS_IMETHODIMP_(nsrefcnt)
 nsCategoryManager::AddRef()
@@ -463,14 +469,13 @@ nsCategoryManager::nsCategoryManager()
 void
 nsCategoryManager::InitMemoryReporter()
 {
-  mReporter = new NS_MEMORY_REPORTER_NAME(CategoryManager);
+  mReporter = new XPCOMCategoryManagerReporter();
   NS_RegisterMemoryReporter(mReporter);
 }
 
 nsCategoryManager::~nsCategoryManager()
 {
-  (void)::NS_UnregisterMemoryReporter(mReporter);
-  mReporter = nullptr;
+  NS_UnregisterMemoryReporter(mReporter);
 
   // the hashtable contains entries that must be deleted before the arena is
   // destroyed, or else you will have PRLocks undestroyed and other Really
@@ -490,11 +495,12 @@ nsCategoryManager::get_category(const char* aName) {
 }
 
 /* static */ int64_t
-nsCategoryManager::GetCategoryManagerSize()
+nsCategoryManager::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf)
 {
-  MOZ_ASSERT(nsCategoryManager::gCategoryManager);
-  return nsCategoryManager::gCategoryManager->SizeOfIncludingThis(
-           CategoryManagerMallocSizeOf);
+  return nsCategoryManager::gCategoryManager
+       ? nsCategoryManager::gCategoryManager->SizeOfIncludingThisHelper(
+          aMallocSizeOf)
+       : 0;
 }
 
 static size_t
@@ -509,7 +515,7 @@ SizeOfCategoryManagerTableEntryExcludingThis(nsDepCharHashKey::KeyType aKey,
 }
 
 size_t
-nsCategoryManager::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf)
+nsCategoryManager::SizeOfIncludingThisHelper(MallocSizeOf aMallocSizeOf)
 {
   size_t n = aMallocSizeOf(this);
 
diff --git a/xpcom/components/nsCategoryManager.h b/xpcom/components/nsCategoryManager.h
index 5f3e3efaad80..8bd632ed5852 100644
--- a/xpcom/components/nsCategoryManager.h
+++ b/xpcom/components/nsCategoryManager.h
@@ -122,8 +122,7 @@ public:
   static nsCategoryManager* GetSingleton();
   static void Destroy();
 
-  static int64_t GetCategoryManagerSize();
-  size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf);
+  static int64_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf);
 
 private:
   static nsCategoryManager* gCategoryManager;
@@ -131,6 +130,8 @@ private:
   nsCategoryManager();
   ~nsCategoryManager();
 
+  size_t SizeOfIncludingThisHelper(mozilla::MallocSizeOf aMallocSizeOf);
+
   CategoryNode* get_category(const char* aName);
   void NotifyObservers(const char* aTopic,
                        const char* aCategoryName, // must be a static string
@@ -141,7 +142,7 @@ private:
   mozilla::Mutex mLock;
   bool mSuppressNotifications;
 
-  nsIMemoryReporter* mReporter;
+  nsCOMPtr<nsIMemoryReporter> mReporter;
 };
 
 #endif
diff --git a/xpcom/components/nsComponentManager.cpp b/xpcom/components/nsComponentManager.cpp
index 3ed89ff3559f..e9cf03a9c70c 100644
--- a/xpcom/components/nsComponentManager.cpp
+++ b/xpcom/components/nsComponentManager.cpp
@@ -1,4 +1,5 @@
-/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim: set ts=8 sts=4 et sw=4 tw=80: */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
@@ -279,22 +280,23 @@ CloneAndAppend(nsIFile* aBase, const nsACString& append)
 // nsComponentManagerImpl
 ////////////////////////////////////////////////////////////////////////////////
 
-NS_MEMORY_REPORTER_MALLOC_SIZEOF_FUN(ComponentManagerMallocSizeOf)
-
-static int64_t
-GetComponentManagerSize()
+class XPCOMComponentManagerReporter MOZ_FINAL : public MemoryReporterBase
 {
-  MOZ_ASSERT(nsComponentManagerImpl::gComponentManager);
-  return nsComponentManagerImpl::gComponentManager->SizeOfIncludingThis(
-           ComponentManagerMallocSizeOf);
-}
-
-NS_MEMORY_REPORTER_IMPLEMENT(ComponentManager,
-    "explicit/xpcom/component-manager",
-    KIND_HEAP,
-    nsIMemoryReporter::UNITS_BYTES,
-    GetComponentManagerSize,
-    "Memory used for the XPCOM component manager.")
+public:
+    XPCOMComponentManagerReporter()
+      : MemoryReporterBase("explicit/xpcom/component-manager",
+                           KIND_HEAP, UNITS_BYTES,
+                           "Memory used for the XPCOM component manager.")
+    {}
+private:
+    int64_t Amount() MOZ_OVERRIDE
+    {
+        return nsComponentManagerImpl::gComponentManager
+             ? nsComponentManagerImpl::gComponentManager->SizeOfIncludingThis(
+                 MallocSizeOf)
+             : 0;
+    }
+};
 
 nsresult
 nsComponentManagerImpl::Create(nsISupports* aOuter, REFNSIID aIID, void** aResult)
@@ -412,8 +414,8 @@ nsresult nsComponentManagerImpl::Init()
 
     nsCategoryManager::GetSingleton()->SuppressNotifications(false);
 
-    mReporter = new NS_MEMORY_REPORTER_NAME(ComponentManager);
-    (void)::NS_RegisterMemoryReporter(mReporter);
+    mReporter = new XPCOMComponentManagerReporter();
+    NS_RegisterMemoryReporter(mReporter);
 
     // Unfortunately, we can't register the nsCategoryManager memory reporter
     // in its constructor (which is triggered by the GetSingleton() call
@@ -798,7 +800,7 @@ nsresult nsComponentManagerImpl::Shutdown(void)
     // Shutdown the component manager
     PR_LOG(nsComponentManagerLog, PR_LOG_DEBUG, ("nsComponentManager: Beginning Shutdown."));
 
-    (void)::NS_UnregisterMemoryReporter(mReporter);
+    NS_UnregisterMemoryReporter(mReporter);
     mReporter = nullptr;
 
     // Release all cached factories
diff --git a/xpcom/components/nsComponentManager.h b/xpcom/components/nsComponentManager.h
index f3c27d1c43d7..1351aa8ec97c 100644
--- a/xpcom/components/nsComponentManager.h
+++ b/xpcom/components/nsComponentManager.h
@@ -38,8 +38,8 @@
 #include "mozilla/Attributes.h"
 
 struct nsFactoryEntry;
-class nsIServiceManager;
 class nsIMemoryReporter;
+class nsIServiceManager;
 struct PRThread;
 
 #define NS_COMPONENTMANAGER_CID                      \
@@ -317,7 +317,7 @@ public:
 private:
     ~nsComponentManagerImpl();
 
-    nsIMemoryReporter* mReporter;
+    nsCOMPtr<nsIMemoryReporter> mReporter;
 };
 
 
diff --git a/xpcom/reflect/xptinfo/public/XPTInterfaceInfoManager.h b/xpcom/reflect/xptinfo/public/XPTInterfaceInfoManager.h
index 74f6dbf45303..3da723e25aa0 100644
--- a/xpcom/reflect/xptinfo/public/XPTInterfaceInfoManager.h
+++ b/xpcom/reflect/xptinfo/public/XPTInterfaceInfoManager.h
@@ -15,6 +15,7 @@
 #include "nsDataHashtable.h"
 
 template<typename T> class nsCOMArray;
+class nsIMemoryReporter;
 class XPTHeader;
 class XPTInterfaceDirectoryEntry;
 class xptiInterfaceEntry;
@@ -108,6 +109,8 @@ private:
 
     xptiWorkingSet               mWorkingSet;
     Mutex                        mResolveLock;
+
+    nsCOMPtr<nsIMemoryReporter>  mReporter;
 };
 
 }
diff --git a/xpcom/reflect/xptinfo/src/xptiInterfaceInfoManager.cpp b/xpcom/reflect/xptinfo/src/xptiInterfaceInfoManager.cpp
index 7ef74dfaaf9f..c34c36b907ca 100644
--- a/xpcom/reflect/xptinfo/src/xptiInterfaceInfoManager.cpp
+++ b/xpcom/reflect/xptinfo/src/xptiInterfaceInfoManager.cpp
@@ -1,4 +1,5 @@
-/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
@@ -19,7 +20,7 @@
 
 using namespace mozilla;
 
-NS_IMPL_ISUPPORTS1(XPTInterfaceInfoManager, 
+NS_IMPL_ISUPPORTS1(XPTInterfaceInfoManager,
                    nsIInterfaceInfoManager)
 
 static XPTInterfaceInfoManager* gInterfaceInfoManager = nullptr;
@@ -27,9 +28,6 @@ static XPTInterfaceInfoManager* gInterfaceInfoManager = nullptr;
 static int gCallCount = 0;
 #endif
 
-
-NS_MEMORY_REPORTER_MALLOC_SIZEOF_FUN(XPTMallocSizeOf)
-
 size_t
 XPTInterfaceInfoManager::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf)
 {
@@ -37,30 +35,33 @@ XPTInterfaceInfoManager::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf)
     ReentrantMonitorAutoEnter monitor(mWorkingSet.mTableReentrantMonitor);
     // The entries themselves are allocated out of an arena accounted
     // for elsewhere, so don't measure them
-    n += mWorkingSet.mIIDTable.SizeOfExcludingThis(NULL, XPTMallocSizeOf);
-    n += mWorkingSet.mNameTable.SizeOfExcludingThis(NULL, XPTMallocSizeOf);
+    n += mWorkingSet.mIIDTable.SizeOfExcludingThis(NULL, aMallocSizeOf);
+    n += mWorkingSet.mNameTable.SizeOfExcludingThis(NULL, aMallocSizeOf);
     return n;
 }
 
-// static
-int64_t
-XPTInterfaceInfoManager::GetXPTIWorkingSetSize()
+class XPTIWorkingSetReporter MOZ_FINAL : public MemoryReporterBase
 {
-    size_t n = XPT_SizeOfArena(gXPTIStructArena, XPTMallocSizeOf);
+public:
+    XPTIWorkingSetReporter()
+      : MemoryReporterBase("explicit/xpti-working-set", KIND_HEAP, UNITS_BYTES,
+                           "Memory used by the XPCOM typelib system.")
+    {}
+private:
+    int64_t Amount() MOZ_OVERRIDE
+    {
+        size_t n = gInterfaceInfoManager
+                 ? gInterfaceInfoManager->SizeOfIncludingThis(MallocSizeOf)
+                 : 0;
 
-    if (gInterfaceInfoManager) {
-        n += gInterfaceInfoManager->SizeOfIncludingThis(XPTMallocSizeOf);
+        // Measure gXPTIStructArena here, too.  This is a bit grotty because it
+        // doesn't belong to the xptiInterfaceInfoManager, but there's no
+        // obviously better place to measure it.
+        n += XPT_SizeOfArena(gXPTIStructArena, MallocSizeOf);
+
+        return n;
     }
-
-    return n;
-}
-
-NS_MEMORY_REPORTER_IMPLEMENT(XPTInterfaceInfoManager,
-                             "explicit/xpti-working-set",
-                             KIND_HEAP,
-                             UNITS_BYTES,
-                             XPTInterfaceInfoManager::GetXPTIWorkingSetSize,
-                             "Memory used by the XPCOM typelib system.")
+};
 
 // static
 XPTInterfaceInfoManager*
@@ -83,7 +84,8 @@ XPTInterfaceInfoManager::XPTInterfaceInfoManager()
     :   mWorkingSet(),
         mResolveLock("XPTInterfaceInfoManager.mResolveLock")
 {
-    NS_RegisterMemoryReporter(new NS_MEMORY_REPORTER_NAME(XPTInterfaceInfoManager));
+    mReporter = new XPTIWorkingSetReporter();
+    NS_RegisterMemoryReporter(mReporter);
 }
 
 XPTInterfaceInfoManager::~XPTInterfaceInfoManager()
@@ -91,6 +93,8 @@ XPTInterfaceInfoManager::~XPTInterfaceInfoManager()
     // We only do this on shutdown of the service.
     mWorkingSet.InvalidateInterfaceInfos();
 
+    NS_UnregisterMemoryReporter(mReporter);
+
     gInterfaceInfoManager = nullptr;
 #ifdef DEBUG
     gCallCount = 0;
diff --git a/xpcom/reflect/xptinfo/src/xptiprivate.h b/xpcom/reflect/xptinfo/src/xptiprivate.h
index 5e718c071a9e..59c66e8823df 100644
--- a/xpcom/reflect/xptinfo/src/xptiprivate.h
+++ b/xpcom/reflect/xptinfo/src/xptiprivate.h
@@ -72,7 +72,6 @@
 /***************************************************************************/
 
 class xptiInterfaceInfo;
-class xptiInterfaceInfoManager;
 class xptiInterfaceEntry;
 class xptiTypelibGuts;