Bug 1245789 - Add abstract thread wrapper for the GMP thread. r=gerald

I need to make GMPParent::Init() async, because the WebIDL JSON parsing
must happen on the main thread, and GMPParent::Init() is called on the
GMP thread, so I need GMPParent::Init() to be async so that in the
Chrome manifest case it can dispatch a task to the main thread to parse
the Chrome manifest before completing. So I'll make GMPParent::Init()
return a promise, and to do that, I need the GMP thread to have an
AbstractThread wrapper.

MozReview-Commit-ID: 44b4Z4jpar8

dom/media/gmp/GMPService.cpp

@@ -357,6 +357,8 @@ GeckoMediaPluginService::GetThread(nsIThread** aThread)
       return rv;
     }
 
+    mAbstractGMPThread = CreateXPCOMAbstractThreadWrapper(mGMPThread, false);
+
     // Tell the thread to initialize plugins
     InitializePlugins();
   }
@@ -367,6 +369,12 @@ GeckoMediaPluginService::GetThread(nsIThread** aThread)
   return NS_OK;
 }
 
+RefPtr<AbstractThread>
+GeckoMediaPluginService::GetAbstractGMPThread()
+{
+  return mAbstractGMPThread;
+}
+
 class GetGMPContentParentForAudioDecoderDone : public GetGMPContentParentCallback
 {
 public:

dom/media/gmp/GMPService.h

@@ -19,6 +19,7 @@
 #include "nsPIDOMWindow.h"
 #include "nsIDocument.h"
 #include "nsIWeakReference.h"
+#include "mozilla/AbstractThread.h"
 
 template <class> struct already_AddRefed;
 
@@ -74,6 +75,8 @@ public:
   void AddPluginCrashedEventTarget(const uint32_t aPluginId,
                                    nsPIDOMWindowInner* aParentWindow);
 
+  RefPtr<AbstractThread> GetAbstractGMPThread();
+
 protected:
   GeckoMediaPluginService();
   virtual ~GeckoMediaPluginService();
@@ -92,6 +95,7 @@ protected:
   Mutex mMutex; // Protects mGMPThread and mGMPThreadShutdown and some members
                 // in derived classes.
   nsCOMPtr<nsIThread> mGMPThread;
+  RefPtr<AbstractThread> mAbstractGMPThread;
   bool mGMPThreadShutdown;
   bool mShuttingDownOnGMPThread;
 

dom/media/platforms/agnostic/eme/EMEDecoderModule.cpp

@@ -161,8 +161,11 @@ private:
 
 class EMEMediaDataDecoderProxy : public MediaDataDecoderProxy {
 public:
-  EMEMediaDataDecoderProxy(nsIThread* aProxyThread, MediaDataDecoderCallback* aCallback, CDMProxy* aProxy, FlushableTaskQueue* aTaskQueue)
-   : MediaDataDecoderProxy(aProxyThread, aCallback)
+  EMEMediaDataDecoderProxy(already_AddRefed<AbstractThread> aProxyThread,
+                           MediaDataDecoderCallback* aCallback,
+                           CDMProxy* aProxy,
+                           FlushableTaskQueue* aTaskQueue)
+   : MediaDataDecoderProxy(Move(aProxyThread), aCallback)
    , mSamplesWaitingForKey(new SamplesWaitingForKey(this, aTaskQueue, aProxy))
    , mProxy(aProxy)
   {
@@ -220,18 +223,16 @@ EMEDecoderModule::~EMEDecoderModule()
 static already_AddRefed<MediaDataDecoderProxy>
 CreateDecoderWrapper(MediaDataDecoderCallback* aCallback, CDMProxy* aProxy, FlushableTaskQueue* aTaskQueue)
 {
-  nsCOMPtr<mozIGeckoMediaPluginService> gmpService = do_GetService("@mozilla.org/gecko-media-plugin-service;1");
-  if (!gmpService) {
+  RefPtr<gmp::GeckoMediaPluginService> s(gmp::GeckoMediaPluginService::GetGeckoMediaPluginService());
+  if (!s) {
     return nullptr;
   }
-
-  nsCOMPtr<nsIThread> thread;
-  nsresult rv = gmpService->GetThread(getter_AddRefs(thread));
-  if (NS_FAILED(rv)) {
+  RefPtr<AbstractThread> thread(s->GetAbstractGMPThread());
+  if (!thread) {
     return nullptr;
   }
-
-  RefPtr<MediaDataDecoderProxy> decoder(new EMEMediaDataDecoderProxy(thread, aCallback, aProxy, aTaskQueue));
+  RefPtr<MediaDataDecoderProxy> decoder(
+    new EMEMediaDataDecoderProxy(thread.forget(), aCallback, aProxy, aTaskQueue));
   return decoder.forget();
 }
 

dom/media/platforms/agnostic/gmp/GMPDecoderModule.cpp

@@ -31,18 +31,15 @@ GMPDecoderModule::~GMPDecoderModule()
 static already_AddRefed<MediaDataDecoderProxy>
 CreateDecoderWrapper(MediaDataDecoderCallback* aCallback)
 {
-  nsCOMPtr<mozIGeckoMediaPluginService> gmpService = do_GetService("@mozilla.org/gecko-media-plugin-service;1");
-  if (!gmpService) {
+  RefPtr<gmp::GeckoMediaPluginService> s(gmp::GeckoMediaPluginService::GetGeckoMediaPluginService());
+  if (!s) {
     return nullptr;
   }
-
-  nsCOMPtr<nsIThread> thread;
-  nsresult rv = gmpService->GetThread(getter_AddRefs(thread));
-  if (NS_FAILED(rv)) {
+  RefPtr<AbstractThread> thread(s->GetAbstractGMPThread());
+  if (!thread) {
     return nullptr;
   }
-
-  RefPtr<MediaDataDecoderProxy> decoder(new MediaDataDecoderProxy(thread, aCallback));
+  RefPtr<MediaDataDecoderProxy> decoder(new MediaDataDecoderProxy(thread.forget(), aCallback));
   return decoder.forget();
 }
 

dom/media/platforms/agnostic/gmp/MediaDataDecoderProxy.cpp

@@ -34,7 +34,7 @@ MediaDataDecoderProxy::Init()
 {
   MOZ_ASSERT(!mIsShutdown);
 
-  return InvokeAsync(mProxyThreadWrapper, this, __func__,
+  return InvokeAsync(mProxyThread, this, __func__,
                      &MediaDataDecoderProxy::InternalInit);
 }
 
@@ -45,8 +45,7 @@ MediaDataDecoderProxy::Input(MediaRawData* aSample)
   MOZ_ASSERT(!mIsShutdown);
 
   nsCOMPtr<nsIRunnable> task(new InputTask(mProxyDecoder, aSample));
-  nsresult rv = mProxyThread->Dispatch(task, NS_DISPATCH_NORMAL);
-  NS_ENSURE_SUCCESS(rv, rv);
+  mProxyThread->Dispatch(task.forget());
 
   return NS_OK;
 }
@@ -61,8 +60,7 @@ MediaDataDecoderProxy::Flush()
 
   nsCOMPtr<nsIRunnable> task;
   task = NS_NewRunnableMethod(mProxyDecoder, &MediaDataDecoder::Flush);
-  nsresult rv = mProxyThread->Dispatch(task, NS_DISPATCH_NORMAL);
-  NS_ENSURE_SUCCESS(rv, rv);
+  mProxyThread->Dispatch(task.forget());
 
   mFlushComplete.WaitUntil(true);
 
@@ -77,8 +75,7 @@ MediaDataDecoderProxy::Drain()
 
   nsCOMPtr<nsIRunnable> task;
   task = NS_NewRunnableMethod(mProxyDecoder, &MediaDataDecoder::Drain);
-  nsresult rv = mProxyThread->Dispatch(task, NS_DISPATCH_NORMAL);
-  NS_ENSURE_SUCCESS(rv, rv);
+  mProxyThread->Dispatch(task.forget());
   return NS_OK;
 }
 
@@ -92,7 +89,7 @@ MediaDataDecoderProxy::Shutdown()
 #endif
   nsCOMPtr<nsIRunnable> task;
   task = NS_NewRunnableMethod(mProxyDecoder, &MediaDataDecoder::Shutdown);
-  nsresult rv = mProxyThread->Dispatch(task, NS_DISPATCH_SYNC);
+  nsresult rv = mProxyThread->AsXPCOMThread()->Dispatch(task, NS_DISPATCH_SYNC);
   NS_ENSURE_SUCCESS(rv, rv);
   return NS_OK;
 }

dom/media/platforms/agnostic/gmp/MediaDataDecoderProxy.h

@@ -11,6 +11,7 @@
 #include "mozilla/RefPtr.h"
 #include "nsThreadUtils.h"
 #include "nscore.h"
+#include "GMPService.h"
 
 namespace mozilla {
 
@@ -62,7 +63,8 @@ class MediaDataDecoderProxy;
 
 class MediaDataDecoderCallbackProxy : public MediaDataDecoderCallback {
 public:
-  MediaDataDecoderCallbackProxy(MediaDataDecoderProxy* aProxyDecoder, MediaDataDecoderCallback* aCallback)
+  MediaDataDecoderCallbackProxy(MediaDataDecoderProxy* aProxyDecoder,
+                                MediaDataDecoderCallback* aCallback)
    : mProxyDecoder(aProxyDecoder)
    , mProxyCallback(aCallback)
   {
@@ -100,7 +102,8 @@ private:
 
 class MediaDataDecoderProxy : public MediaDataDecoder {
 public:
-  MediaDataDecoderProxy(nsIThread* aProxyThread, MediaDataDecoderCallback* aCallback)
+  MediaDataDecoderProxy(already_AddRefed<AbstractThread> aProxyThread,
+                        MediaDataDecoderCallback* aCallback)
    : mProxyThread(aProxyThread)
    , mProxyCallback(this, aCallback)
    , mFlushComplete(false)
@@ -108,7 +111,6 @@ public:
    , mIsShutdown(false)
 #endif
   {
-    mProxyThreadWrapper = CreateXPCOMAbstractThreadWrapper(aProxyThread, false);
   }
 
   // Ideally, this would return a regular MediaDataDecoderCallback pointer
@@ -151,7 +153,7 @@ private:
 
 #ifdef DEBUG
   bool IsOnProxyThread() {
-    return NS_GetCurrentThread() == mProxyThread;
+    return mProxyThread && mProxyThread->IsCurrentThreadIn();
   }
 #endif
 
@@ -159,8 +161,7 @@ private:
   friend class InitTask;
 
   RefPtr<MediaDataDecoder> mProxyDecoder;
-  nsCOMPtr<nsIThread> mProxyThread;
-  RefPtr<AbstractThread> mProxyThreadWrapper;
+  RefPtr<AbstractThread> mProxyThread;
 
   MediaDataDecoderCallbackProxy mProxyCallback;