diff --git a/content/base/src/nsDOMLists.cpp b/content/base/src/DOMStringList.cpp
similarity index 57%
rename from content/base/src/nsDOMLists.cpp
rename to content/base/src/DOMStringList.cpp
index 6c1f942cc289..10a5c10e5248 100644
--- a/content/base/src/nsDOMLists.cpp
+++ b/content/base/src/DOMStringList.cpp
@@ -3,35 +3,34 @@
  * 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/. */
 
-/*
- * Implementation of nsIDOMDOMStringList, used by various DOM stuff.
- */
-
-#include "nsDOMLists.h"
+#include "mozilla/dom/DOMStringList.h"
 #include "nsError.h"
 #include "nsDOMClassInfoID.h"
 #include "nsINode.h"
 
-nsDOMStringList::nsDOMStringList()
+DOMCI_DATA(DOMStringList, mozilla::dom::DOMStringList)
+
+namespace mozilla {
+namespace dom {
+
+DOMStringList::DOMStringList()
 {
 }
 
-nsDOMStringList::~nsDOMStringList()
+DOMStringList::~DOMStringList()
 {
 }
 
-DOMCI_DATA(DOMStringList, nsDOMStringList)
-
-NS_IMPL_ADDREF(nsDOMStringList)
-NS_IMPL_RELEASE(nsDOMStringList)
-NS_INTERFACE_TABLE_HEAD(nsDOMStringList)
-  NS_INTERFACE_TABLE1(nsDOMStringList, nsIDOMDOMStringList)
+NS_IMPL_ADDREF(DOMStringList)
+NS_IMPL_RELEASE(DOMStringList)
+NS_INTERFACE_TABLE_HEAD(DOMStringList)
+  NS_INTERFACE_TABLE1(DOMStringList, nsIDOMDOMStringList)
   NS_INTERFACE_TABLE_TO_MAP_SEGUE
   NS_DOM_INTERFACE_MAP_ENTRY_CLASSINFO(DOMStringList)
 NS_INTERFACE_MAP_END
 
 NS_IMETHODIMP
-nsDOMStringList::Item(uint32_t aIndex, nsAString& aResult)
+DOMStringList::Item(uint32_t aIndex, nsAString& aResult)
 {
   if (aIndex >= mNames.Length()) {
     SetDOMStringToNull(aResult);
@@ -43,7 +42,7 @@ nsDOMStringList::Item(uint32_t aIndex, nsAString& aResult)
 }
 
 NS_IMETHODIMP
-nsDOMStringList::GetLength(uint32_t *aLength)
+DOMStringList::GetLength(uint32_t *aLength)
 {
   *aLength = mNames.Length();
 
@@ -51,9 +50,12 @@ nsDOMStringList::GetLength(uint32_t *aLength)
 }
 
 NS_IMETHODIMP
-nsDOMStringList::Contains(const nsAString& aString, bool *aResult)
+DOMStringList::Contains(const nsAString& aString, bool *aResult)
 {
   *aResult = mNames.Contains(aString);
 
   return NS_OK;
 }
+
+} // namespace dom
+} // namespace mozilla
diff --git a/content/base/src/nsDOMLists.h b/content/base/src/DOMStringList.h
similarity index 72%
rename from content/base/src/nsDOMLists.h
rename to content/base/src/DOMStringList.h
index ef18c5060035..b2f9cf70a2ac 100644
--- a/content/base/src/nsDOMLists.h
+++ b/content/base/src/DOMStringList.h
@@ -7,18 +7,21 @@
  * Implementation of nsIDOMDOMStringList, used by various DOM stuff.
  */
 
-#ifndef nsDOMLists_h___
-#define nsDOMLists_h___
+#ifndef mozilla_dom_DOMStringList_h
+#define mozilla_dom_DOMStringList_h
 
 #include "nsIDOMDOMStringList.h"
 #include "nsTArray.h"
 #include "nsString.h"
 
-class nsDOMStringList : public nsIDOMDOMStringList
+namespace mozilla {
+namespace dom {
+
+class DOMStringList : public nsIDOMDOMStringList
 {
 public:
-  nsDOMStringList();
-  virtual ~nsDOMStringList();
+  DOMStringList();
+  virtual ~DOMStringList();
 
   NS_DECL_ISUPPORTS
   NS_DECL_NSIDOMDOMSTRINGLIST
@@ -42,4 +45,7 @@ private:
   nsTArray<nsString> mNames;
 };
 
-#endif /* nsDOMLists_h___ */
+} // namespace dom
+} // namespace mozilla
+
+#endif /* mozilla_dom_DOMStringList_h */
diff --git a/content/base/src/WebSocket.cpp b/content/base/src/WebSocket.cpp
index feb10e13533e..9e1a83a31c2f 100644
--- a/content/base/src/WebSocket.cpp
+++ b/content/base/src/WebSocket.cpp
@@ -36,7 +36,7 @@
 #include "nsNetUtil.h"
 #include "nsILoadGroup.h"
 #include "mozilla/Preferences.h"
-#include "nsDOMLists.h"
+#include "mozilla/dom/DOMStringList.h"
 #include "xpcpublic.h"
 #include "nsContentPolicyUtils.h"
 #include "nsDOMFile.h"
diff --git a/content/base/src/moz.build b/content/base/src/moz.build
index 61ed489b81c7..4e97be3c0ac8 100644
--- a/content/base/src/moz.build
+++ b/content/base/src/moz.build
@@ -62,6 +62,7 @@ EXPORTS.mozilla.dom += [
     'DOMImplementation.h',
     'DOMParser.h',
     'DOMRect.h',
+    'DOMStringList.h',
     'EventSource.h',
     'Link.h',
     'NodeIterator.h',
@@ -80,6 +81,7 @@ UNIFIED_SOURCES += [
     'DOMImplementation.cpp',
     'DOMParser.cpp',
     'DOMRect.cpp',
+    'DOMStringList.cpp',
     'Element.cpp',
     'EventSource.cpp',
     'FileIOObject.cpp',
@@ -107,7 +109,6 @@ UNIFIED_SOURCES += [
     'nsDOMCaretPosition.cpp',
     'nsDOMFile.cpp',
     'nsDOMFileReader.cpp',
-    'nsDOMLists.cpp',
     'nsDOMMutationObserver.cpp',
     'nsDOMSerializer.cpp',
     'nsDOMSettableTokenList.cpp',
diff --git a/content/base/src/nsDocument.cpp b/content/base/src/nsDocument.cpp
index 1c05a2a2193a..19c4574e8f63 100644
--- a/content/base/src/nsDocument.cpp
+++ b/content/base/src/nsDocument.cpp
@@ -1307,7 +1307,7 @@ nsExternalResourceMap::ExternalResource::~ExternalResource()
 // ==================================================================
 
 // If we ever have an nsIDocumentObserver notification for stylesheet title
-// changes, we could make this inherit from nsDOMStringList instead of
+// changes, we could make this inherit from DOMStringList instead of
 // reimplementing nsIDOMDOMStringList.
 class nsDOMStyleSheetSetList MOZ_FINAL : public nsIDOMDOMStringList
 {
diff --git a/content/base/src/nsFrameMessageManager.cpp b/content/base/src/nsFrameMessageManager.cpp
index 2e7e6d98b9d2..def59816f903 100644
--- a/content/base/src/nsFrameMessageManager.cpp
+++ b/content/base/src/nsFrameMessageManager.cpp
@@ -33,7 +33,7 @@
 #include "mozilla/dom/StructuredCloneUtils.h"
 #include "JavaScriptChild.h"
 #include "JavaScriptParent.h"
-#include "nsDOMLists.h"
+#include "mozilla/dom/DOMStringList.h"
 #include "nsPrintfCString.h"
 #include <algorithm>
 
diff --git a/content/html/content/src/HTMLPropertiesCollection.cpp b/content/html/content/src/HTMLPropertiesCollection.cpp
index d315063e0331..dd9ccced74b2 100644
--- a/content/html/content/src/HTMLPropertiesCollection.cpp
+++ b/content/html/content/src/HTMLPropertiesCollection.cpp
@@ -492,7 +492,7 @@ PropertyNodeList::EnsureFresh()
 }
 
 PropertyStringList::PropertyStringList(HTMLPropertiesCollection* aCollection)
-  : nsDOMStringList()
+  : DOMStringList()
   , mCollection(aCollection)
 { }
 
@@ -511,21 +511,21 @@ NS_IMETHODIMP
 PropertyStringList::Item(uint32_t aIndex, nsAString& aResult)
 {
   mCollection->EnsureFresh();
-  return nsDOMStringList::Item(aIndex, aResult);
+  return DOMStringList::Item(aIndex, aResult);
 }
 
 NS_IMETHODIMP
 PropertyStringList::GetLength(uint32_t* aLength)
 {
   mCollection->EnsureFresh();
-  return nsDOMStringList::GetLength(aLength);
+  return DOMStringList::GetLength(aLength);
 }
 
 NS_IMETHODIMP
 PropertyStringList::Contains(const nsAString& aString, bool* aResult)
 {
   mCollection->EnsureFresh();
-  return nsDOMStringList::Contains(aString, aResult);
+  return DOMStringList::Contains(aString, aResult);
 }
 
 bool
@@ -533,7 +533,7 @@ PropertyStringList::ContainsInternal(const nsAString& aString)
 {
   // This method should not call EnsureFresh, otherwise we may become stuck in an infinite loop.
   bool result;
-  nsDOMStringList::Contains(aString, &result);
+  DOMStringList::Contains(aString, &result);
   return result;
 }
 
diff --git a/content/html/content/src/HTMLPropertiesCollection.h b/content/html/content/src/HTMLPropertiesCollection.h
index df42fd136344..1328efa00924 100644
--- a/content/html/content/src/HTMLPropertiesCollection.h
+++ b/content/html/content/src/HTMLPropertiesCollection.h
@@ -8,7 +8,7 @@
 #define HTMLPropertiesCollection_h_
 
 #include "mozilla/Attributes.h"
-#include "nsDOMLists.h"
+#include "mozilla/dom/DOMStringList.h"
 #include "nsCycleCollectionParticipant.h"
 #include "nsAutoPtr.h"
 #include "nsCOMArray.h"
@@ -31,7 +31,7 @@ class HTMLPropertiesCollection;
 class PropertyNodeList;
 class Element;
 
-class PropertyStringList : public nsDOMStringList
+class PropertyStringList : public DOMStringList
 {
 public:
   PropertyStringList(HTMLPropertiesCollection* aCollection);
@@ -86,7 +86,7 @@ public:
     aFound = IsSupportedNamedProperty(aName);
     return aFound ? NamedItem(aName) : nullptr;
   }
-  nsDOMStringList* Names()
+  DOMStringList* Names()
   {
     EnsureFresh();
     return mNames;
diff --git a/dom/events/DataTransfer.cpp b/dom/events/DataTransfer.cpp
index 8c0b5536d157..04b88e3aa029 100644
--- a/dom/events/DataTransfer.cpp
+++ b/dom/events/DataTransfer.cpp
@@ -13,7 +13,7 @@
 #include "nsIVariant.h"
 #include "nsISupportsPrimitives.h"
 #include "nsIScriptSecurityManager.h"
-#include "nsDOMLists.h"
+#include "mozilla/dom/DOMStringList.h"
 #include "nsError.h"
 #include "nsIDragService.h"
 #include "nsIClipboard.h"
@@ -327,7 +327,7 @@ DataTransfer::GetFiles(nsIDOMFileList** aFileList)
 already_AddRefed<nsIDOMDOMStringList>
 DataTransfer::Types()
 {
-  nsRefPtr<nsDOMStringList> types = new nsDOMStringList();
+  nsRefPtr<DOMStringList> types = new DOMStringList();
   if (mItems.Length()) {
     const nsTArray<TransferItem>& item = mItems[0];
     for (uint32_t i = 0; i < item.Length(); i++)
@@ -531,7 +531,7 @@ DataTransfer::MozTypesAt(uint32_t aIndex, ErrorResult& aRv)
     return nullptr;
   }
 
-  nsRefPtr<nsDOMStringList> types = new nsDOMStringList();
+  nsRefPtr<DOMStringList> types = new DOMStringList();
   if (aIndex < mItems.Length()) {
     // note that you can retrieve the types regardless of their principal
     nsTArray<TransferItem>& item = mItems[aIndex];
diff --git a/dom/indexedDB/IDBDatabase.cpp b/dom/indexedDB/IDBDatabase.cpp
index 099cab84dd83..990c7ba47894 100644
--- a/dom/indexedDB/IDBDatabase.cpp
+++ b/dom/indexedDB/IDBDatabase.cpp
@@ -12,9 +12,9 @@
 #include "mozilla/Mutex.h"
 #include "mozilla/storage.h"
 #include "mozilla/dom/ContentParent.h"
+#include "mozilla/dom/DOMStringList.h"
 #include "mozilla/dom/quota/Client.h"
 #include "mozilla/dom/quota/QuotaManager.h"
-#include "nsDOMLists.h"
 #include "nsJSUtils.h"
 #include "nsProxyRelease.h"
 #include "nsThreadUtils.h"
@@ -508,7 +508,7 @@ IDBDatabase::GetObjectStoreNames(ErrorResult& aRv) const
     return nullptr;
   }
 
-  nsRefPtr<nsDOMStringList> list(new nsDOMStringList());
+  nsRefPtr<DOMStringList> list(new DOMStringList());
   uint32_t count = objectStoreNames.Length();
   for (uint32_t index = 0; index < count; index++) {
     if (!list->Add(objectStoreNames[index])) {
diff --git a/dom/indexedDB/IDBObjectStore.cpp b/dom/indexedDB/IDBObjectStore.cpp
index e7088582aea5..ba6a555921c2 100644
--- a/dom/indexedDB/IDBObjectStore.cpp
+++ b/dom/indexedDB/IDBObjectStore.cpp
@@ -24,7 +24,7 @@
 #include "nsContentUtils.h"
 #include "nsDOMClassInfo.h"
 #include "nsDOMFile.h"
-#include "nsDOMLists.h"
+#include "mozilla/dom/DOMStringList.h"
 #include "nsEventDispatcher.h"
 #include "nsJSUtils.h"
 #include "nsServiceManagerUtils.h"
@@ -2642,7 +2642,7 @@ IDBObjectStore::GetIndexNames(ErrorResult& aRv)
 {
   NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
 
-  nsRefPtr<nsDOMStringList> list(new nsDOMStringList());
+  nsRefPtr<DOMStringList> list(new DOMStringList());
 
   nsAutoTArray<nsString, 10> names;
   uint32_t count = mInfo->indexes.Length();
diff --git a/dom/indexedDB/IDBTransaction.cpp b/dom/indexedDB/IDBTransaction.cpp
index ef5c2416e6b8..6cf4870dbc80 100644
--- a/dom/indexedDB/IDBTransaction.cpp
+++ b/dom/indexedDB/IDBTransaction.cpp
@@ -14,7 +14,7 @@
 #include "mozilla/dom/quota/QuotaManager.h"
 #include "mozilla/storage.h"
 #include "nsDOMClassInfoID.h"
-#include "nsDOMLists.h"
+#include "mozilla/dom/DOMStringList.h"
 #include "nsEventDispatcher.h"
 #include "nsPIDOMWindow.h"
 #include "nsProxyRelease.h"
@@ -676,7 +676,7 @@ IDBTransaction::GetObjectStoreNames(ErrorResult& aRv)
 {
   NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
 
-  nsRefPtr<nsDOMStringList> list(new nsDOMStringList());
+  nsRefPtr<DOMStringList> list(new DOMStringList());
 
   nsAutoTArray<nsString, 10> stackArray;
   nsTArray<nsString>* arrayOfNames;
diff --git a/dom/src/offline/nsDOMOfflineResourceList.cpp b/dom/src/offline/nsDOMOfflineResourceList.cpp
index 95577fc820df..a74d25f6baf5 100644
--- a/dom/src/offline/nsDOMOfflineResourceList.cpp
+++ b/dom/src/offline/nsDOMOfflineResourceList.cpp
@@ -6,7 +6,7 @@
 #include "nsDOMOfflineResourceList.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsError.h"
-#include "nsDOMLists.h"
+#include "mozilla/dom/DOMStringList.h"
 #include "nsIPrefetchService.h"
 #include "nsCPrefetchService.h"
 #include "nsNetUtil.h"
@@ -189,7 +189,7 @@ nsDOMOfflineResourceList::GetMozItems(nsIDOMDOMStringList **aItems)
 
   *aItems = nullptr;
 
-  nsRefPtr<nsDOMStringList> items = new nsDOMStringList();
+  nsRefPtr<DOMStringList> items = new DOMStringList();
 
   // If we are not associated with an application cache, return an
   // empty list.