Bug 1116358 - Directly call Release() on |this| when closing a GMP encoder/decoder proxies; r=cpearce

This is needed in order to avoid calling Release() on a smart pointer.

dom/media/gmp/GMPAudioDecoderParent.cpp

@@ -149,7 +149,7 @@ GMPAudioDecoderParent::Close()
 
   // In case this is the last reference
   nsRefPtr<GMPAudioDecoderParent> kungfudeathgrip(this);
-  NS_RELEASE(kungfudeathgrip);
+  Release();
   Shutdown();
 
   return NS_OK;

dom/media/gmp/GMPVideoDecoderParent.cpp

@@ -76,7 +76,7 @@ GMPVideoDecoderParent::Close()
 
   // In case this is the last reference
   nsRefPtr<GMPVideoDecoderParent> kungfudeathgrip(this);
-  NS_RELEASE(kungfudeathgrip);
+  Release();
   Shutdown();
 }
 

dom/media/gmp/GMPVideoEncoderParent.cpp

@@ -91,7 +91,7 @@ GMPVideoEncoderParent::Close()
 
   // In case this is the last reference
   nsRefPtr<GMPVideoEncoderParent> kungfudeathgrip(this);
-  NS_RELEASE(kungfudeathgrip);
+  Release();
   Shutdown();
 }