Bug 1490415 - prevent creating a GPUVideoTextureHost with a null wrapped texture; r=sotaro

Differential Revision: https://phabricator.services.mozilla.com/D5563

gfx/layers/composite/GPUVideoTextureHost.cpp

@@ -13,11 +13,11 @@ namespace mozilla {
 namespace layers {
 
 GPUVideoTextureHost::GPUVideoTextureHost(TextureFlags aFlags,
-                                         const SurfaceDescriptorGPUVideo& aDescriptor)
+                                         TextureHost* aWrappedTextureHost)
   : TextureHost(aFlags)
+  , mWrappedTextureHost(aWrappedTextureHost)
 {
   MOZ_COUNT_CTOR(GPUVideoTextureHost);
-  mWrappedTextureHost = VideoBridgeParent::GetSingleton()->LookupTexture(aDescriptor.handle());
 }
 
 GPUVideoTextureHost::~GPUVideoTextureHost()
@@ -25,6 +25,19 @@ GPUVideoTextureHost::~GPUVideoTextureHost()
   MOZ_COUNT_DTOR(GPUVideoTextureHost);
 }
 
+GPUVideoTextureHost*
+GPUVideoTextureHost::CreateFromDescriptor(
+  TextureFlags aFlags,
+  const SurfaceDescriptorGPUVideo& aDescriptor)
+{
+  TextureHost* wrappedTextureHost =
+    VideoBridgeParent::GetSingleton()->LookupTexture(aDescriptor.handle());
+  if (!wrappedTextureHost) {
+    return nullptr;
+  }
+  return new GPUVideoTextureHost(aFlags, wrappedTextureHost);
+}
+
 bool
 GPUVideoTextureHost::Lock()
 {

gfx/layers/composite/GPUVideoTextureHost.h

@@ -15,8 +15,10 @@ namespace layers {
 class GPUVideoTextureHost : public TextureHost
 {
 public:
- GPUVideoTextureHost(TextureFlags aFlags,
+  static GPUVideoTextureHost* CreateFromDescriptor(
+    TextureFlags aFlags,
     const SurfaceDescriptorGPUVideo& aDescriptor);
+
   virtual ~GPUVideoTextureHost();
 
   virtual void DeallocateDeviceData() override {}
@@ -65,6 +67,8 @@ public:
   virtual bool SupportsWrNativeTexture() override;
 
 protected:
+  GPUVideoTextureHost(TextureFlags aFlags, TextureHost* aWrappedTextureHost);
+
   RefPtr<TextureHost> mWrappedTextureHost;
 };
 

gfx/layers/composite/TextureHost.cpp

@@ -336,7 +336,8 @@ CreateBackendIndependentTextureHost(const SurfaceDescriptor& aDesc,
       break;
     }
     case SurfaceDescriptor::TSurfaceDescriptorGPUVideo: {
-      result = new GPUVideoTextureHost(aFlags, aDesc.get_SurfaceDescriptorGPUVideo());
+      result = GPUVideoTextureHost::CreateFromDescriptor(
+        aFlags, aDesc.get_SurfaceDescriptorGPUVideo());
       break;
     }
 #ifdef XP_WIN