Bug 1214967 - Proxy observer service notification across to content process when GMPs are added/removed. r=billm,jwwang

dom/ipc/ContentChild.cpp

@@ -195,6 +195,7 @@
 #include "mozilla/widget/PuppetBidiKeyboard.h"
 #include "mozilla/RemoteSpellCheckEngineChild.h"
 #include "GMPServiceChild.h"
+#include "GMPDecoderModule.h"
 #include "gfxPlatform.h"
 #include "nscore.h" // for NS_FREE_PERMANENT_DATA
 
@@ -1463,6 +1464,13 @@ ContentChild::RecvNotifyPresentationReceiverCleanUp(const nsString& aSessionId)
   return true;
 }
 
+bool
+ContentChild::RecvNotifyGMPsChanged()
+{
+  GMPDecoderModule::UpdateUsableCodecs();
+  return true;
+}
+
 PCrashReporterChild*
 ContentChild::AllocPCrashReporterChild(const mozilla::dom::NativeThreadId& id,
                                        const uint32_t& processType)

dom/ipc/ContentChild.h

@@ -287,6 +287,8 @@ public:
                                                         const nsString& aSessionId) override;
     virtual bool RecvNotifyPresentationReceiverCleanUp(const nsString& aSessionId) override;
 
+    virtual bool RecvNotifyGMPsChanged() override;
+
     virtual PSpeechSynthesisChild* AllocPSpeechSynthesisChild() override;
     virtual bool DeallocPSpeechSynthesisChild(PSpeechSynthesisChild* aActor) override;
 

dom/ipc/ContentParent.cpp

@@ -692,6 +692,7 @@ static const char* sObserverTopics[] = {
     "profiler-subprocess-gather",
     "profiler-subprocess",
 #endif
+    "gmp-changed",
 };
 
 #ifdef MOZ_NUWA_PROCESS
@@ -3293,6 +3294,9 @@ ContentParent::Observe(nsISupports* aSubject,
             }
         }
     }
+    else if (!strcmp(aTopic, "gmp-changed")) {
+      unused << SendNotifyGMPsChanged();
+    }
 #endif
     return NS_OK;
 }

dom/ipc/PContent.ipdl

@@ -677,6 +677,11 @@ child:
      */
     async NotifyPresentationReceiverCleanUp(nsString aSessionId);
 
+    /**
+     * Notify the child that the Gecko Media Plugins installed changed.
+     */
+    async NotifyGMPsChanged();
+
 parent:
     /**
      * Tell the content process some attributes of itself.  This is

dom/media/gmp/GMPServiceParent.cpp

@@ -42,6 +42,7 @@
 #include "nsPrintfCString.h"
 #endif
 #include "nsIXULRuntime.h"
+#include "GMPDecoderModule.h"
 #include <limits>
 
 namespace mozilla {
@@ -700,6 +701,27 @@ GeckoMediaPluginServiceParent::LoadFromEnvironment()
   mScannedPluginOnDisk = true;
 }
 
+class NotifyObserversTask final : public nsRunnable {
+public:
+  explicit NotifyObserversTask(const char* aTopic, nsString aData = EmptyString())
+    : mTopic(aTopic)
+    , mData(aData)
+  {}
+  NS_IMETHOD Run() override {
+    MOZ_ASSERT(NS_IsMainThread());
+    nsCOMPtr<nsIObserverService> obsService = mozilla::services::GetObserverService();
+    MOZ_ASSERT(obsService);
+    if (obsService) {
+      obsService->NotifyObservers(nullptr, mTopic, mData.get());
+    }
+    return NS_OK;
+  }
+private:
+  ~NotifyObserversTask() {}
+  const char* mTopic;
+  const nsString mData;
+};
+
 NS_IMETHODIMP
 GeckoMediaPluginServiceParent::PathRunnable::Run()
 {
@@ -710,6 +732,14 @@ GeckoMediaPluginServiceParent::PathRunnable::Run()
                                 mOperation == REMOVE_AND_DELETE_FROM_DISK,
                                 mDefer);
   }
+  // For e10s, we must fire a notification so that all ContentParents notify
+  // their children to update the codecs that the GMPDecoderModule can use.
+  NS_DispatchToMainThread(new NotifyObserversTask("gmp-changed"), NS_DISPATCH_NORMAL);
+  // For non-e10s, and for decoding in the chrome process, must update GMP
+  // PDM's codecs list directly.
+  NS_DispatchToMainThread(NS_NewRunnableFunction([]() -> void {
+    GMPDecoderModule::UpdateUsableCodecs();
+  }));
   return NS_OK;
 }
 
@@ -935,27 +965,6 @@ GeckoMediaPluginServiceParent::ClonePlugin(const GMPParent* aOriginal)
   return gmp.get();
 }
 
-class NotifyObserversTask final : public nsRunnable {
-public:
-  explicit NotifyObserversTask(const char* aTopic, nsString aData = EmptyString())
-    : mTopic(aTopic)
-    , mData(aData)
-  {}
-  NS_IMETHOD Run() override {
-    MOZ_ASSERT(NS_IsMainThread());
-    nsCOMPtr<nsIObserverService> obsService = mozilla::services::GetObserverService();
-    MOZ_ASSERT(obsService);
-    if (obsService) {
-      obsService->NotifyObservers(nullptr, mTopic, mData.get());
-    }
-    return NS_OK;
-  }
-private:
-  ~NotifyObserversTask() {}
-  const char* mTopic;
-  const nsString mData;
-};
-
 void
 GeckoMediaPluginServiceParent::AddOnGMPThread(const nsAString& aDirectory)
 {