Bug 1551615 - Make PGMPContent protocol refcounted. r=nika

Differential Revision: https://phabricator.services.mozilla.com/D68904

dom/media/gmp/GMPChild.cpp

@@ -651,12 +651,9 @@ mozilla::ipc::IPCResult GMPChild::RecvInitGMPContentChild(
 
 void GMPChild::GMPContentChildActorDestroy(GMPContentChild* aGMPContentChild) {
   for (uint32_t i = mGMPContentChildren.Length(); i > 0; i--) {
-    UniquePtr<GMPContentChild>& toDestroy = mGMPContentChildren[i - 1];
-    if (toDestroy.get() == aGMPContentChild) {
+    RefPtr<GMPContentChild>& destroyedActor = mGMPContentChildren[i - 1];
+    if (destroyedActor.get() == aGMPContentChild) {
       SendPGMPContentChildDestroyed();
-      RefPtr<DeleteTask<GMPContentChild>> task =
-          new DeleteTask<GMPContentChild>(toDestroy.release());
-      MessageLoop::current()->PostTask(task.forget());
       mGMPContentChildren.RemoveElementAt(i - 1);
       break;
     }

dom/media/gmp/GMPChild.h

@@ -69,7 +69,7 @@ class GMPChild : public PGMPChild {
 
   nsTArray<std::pair<nsCString, nsCString>> MakeCDMHostVerificationPaths();
 
-  nsTArray<UniquePtr<GMPContentChild>> mGMPContentChildren;
+  nsTArray<RefPtr<GMPContentChild>> mGMPContentChildren;
 
   RefPtr<GMPTimerChild> mTimerChild;
   RefPtr<GMPStorageChild> mStorage;

dom/media/gmp/GMPContentChild.cpp

@@ -14,12 +14,6 @@
 namespace mozilla {
 namespace gmp {
 
-GMPContentChild::GMPContentChild(GMPChild* aChild) : mGMPChild(aChild) {
-  MOZ_COUNT_CTOR(GMPContentChild);
-}
-
-GMPContentChild::~GMPContentChild() { MOZ_COUNT_DTOR(GMPContentChild); }
-
 MessageLoop* GMPContentChild::GMPMessageLoop() {
   return mGMPChild->GMPMessageLoop();
 }

dom/media/gmp/GMPContentChild.h

@@ -16,8 +16,11 @@ class GMPChild;
 
 class GMPContentChild : public PGMPContentChild, public GMPSharedMem {
  public:
-  explicit GMPContentChild(GMPChild* aChild);
-  virtual ~GMPContentChild();
+  // Mark AddRef and Release as `final`, as they overload pure virtual
+  // implementations in PGMPContentChild.
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(GMPContentChild, final)
+
+  explicit GMPContentChild(GMPChild* aChild) : mGMPChild(aChild) {}
 
   MessageLoop* GMPMessageLoop();
 
@@ -45,6 +48,9 @@ class GMPContentChild : public PGMPContentChild, public GMPSharedMem {
   bool IsUsed();
 
   GMPChild* mGMPChild;
+
+ private:
+  ~GMPContentChild() = default;
 };
 
 }  // namespace gmp

dom/media/gmp/GMPContentParent.cpp

@@ -42,23 +42,11 @@ GMPContentParent::~GMPContentParent() {
       GetBoolString(mChromiumCDMs.IsEmpty()), mCloseBlockerCount);
 }
 
-class ReleaseGMPContentParent : public Runnable {
- public:
-  explicit ReleaseGMPContentParent(GMPContentParent* aToRelease)
-      : Runnable("gmp::ReleaseGMPContentParent"), mToRelease(aToRelease) {}
-
-  NS_IMETHOD Run() override { return NS_OK; }
-
- private:
-  RefPtr<GMPContentParent> mToRelease;
-};
-
 void GMPContentParent::ActorDestroy(ActorDestroyReason aWhy) {
   GMP_LOG_DEBUG("GMPContentParent::ActorDestroy(this=%p, aWhy=%d)", this,
                 static_cast<int>(aWhy));
   MOZ_ASSERT(mVideoDecoders.IsEmpty() && mVideoEncoders.IsEmpty() &&
              mChromiumCDMs.IsEmpty());
-  NS_DispatchToCurrentThread(new ReleaseGMPContentParent(this));
 }
 
 void GMPContentParent::CheckThread() {

dom/media/gmp/GMPContentParent.h

@@ -22,7 +22,9 @@ class GMPContentParent final : public PGMPContentParent, public GMPSharedMem {
   friend class PGMPContentParent;
 
  public:
-  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(GMPContentParent)
+  // Mark AddRef and Release as `final`, as they overload pure virtual
+  // implementations in PGMPContentParent.
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(GMPContentParent, final)
 
   explicit GMPContentParent(GMPParent* aParent = nullptr);
 

dom/media/gmp/PGMPContent.ipdl

@@ -10,7 +10,7 @@ include protocol PChromiumCDM;
 namespace mozilla {
 namespace gmp {
 
-intr protocol PGMPContent
+intr refcounted protocol PGMPContent
 {
   manages PGMPVideoDecoder;
   manages PGMPVideoEncoder;