Change the cpp wrappers of audio input/video capture to use CompletionCallbackWithOutput.

ppapi/cpp/array_output.h

Index: ppapi/cpp/array_output.h
diff --git a/ppapi/cpp/array_output.h b/ppapi/cpp/array_output.h
index 708150757d67dcc4ff354756759b72dfdebdf6bd..57fa79014061fc95ad9e9ce3a6e49ce81b01f5d3 100644
--- a/ppapi/cpp/array_output.h
+++ b/ppapi/cpp/array_output.h
@@ -201,6 +201,7 @@ class ArrayOutputAdapterWithStorage : public ArrayOutputAdapter<T> {
 class VarArrayOutputAdapterWithStorage : public ArrayOutputAdapter<PP_Var> {
  public:
   VarArrayOutputAdapterWithStorage();
+  virtual ~VarArrayOutputAdapterWithStorage();
 
   // Returns the final array of resource objects, converting the PP_Vars
   // written by the browser to pp::Var objects.
@@ -237,6 +238,13 @@ class ResourceArrayOutputAdapterWithStorage
     set_output(&temp_storage_);
   }
 
+  virtual ~ResourceArrayOutputAdapterWithStorage() {
+    if (!temp_storage_.empty()) {
+      // An easy way to release the resource references held by this object.
+      output();
+    }
+  }
+
   // Returns the final array of resource objects, converting the PP_Resources
   // written by the browser to resource objects.
   //