Make WebTaskRunner ThreadSafeRefCounted

third_party/WebKit/Source/platform/graphics/TextureHolder.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef TextureHolder_h
 #define TextureHolder_h
 
 #include "gpu/command_buffer/common/mailbox.h"
 #include "gpu/command_buffer/common/sync_token.h"
 #include "platform/PlatformExport.h"
@@ skipping 27 matching lines @@
   }
   virtual void updateSyncToken(gpu::SyncToken) { NOTREACHED(); }
 
   // Methods overrided by SkiaTextureHolder
   virtual sk_sp<SkImage> skImage() {
     NOTREACHED();
     return nullptr;
   }
   virtual void setSharedContextId(unsigned) { NOTREACHED(); }
   virtual void setImageThread(WebThread*) { NOTREACHED(); }
-  virtual void setImageThreadTaskRunner(std::unique_ptr<WebTaskRunner>) {
-    NOTREACHED();
-  }
+  virtual void setImageThreadTaskRunner(RefPtr<WebTaskRunner>) { NOTREACHED(); }
 
   // Methods that have exactly the same impelmentation for all sub-classes
   bool wasTransferred() { return m_wasTransferred; }
-  WebTaskRunner* textureThreadTaskRunner() {
-    return m_textureThreadTaskRunner.get();
+  RefPtr<WebTaskRunner> textureThreadTaskRunner() {
+    return m_textureThreadTaskRunner;
   }
   void setWasTransferred(bool flag) { m_wasTransferred = flag; }
-  void setTextureThreadTaskRunner(std::unique_ptr<WebTaskRunner> taskRunner) {
+  void setTextureThreadTaskRunner(RefPtr<WebTaskRunner> taskRunner) {
     m_textureThreadTaskRunner = std::move(taskRunner);
   }
 
  private:
   // Wether the AcceleratedStaticBitmapImage that holds the |m_texture| was
   // transferred to another thread or not. Set to false when the
   // AcceleratedStaticBitmapImage remain on the same thread as it was craeted.
   bool m_wasTransferred = false;
   // Keep a clone of the WebTaskRunner. This is to handle the case where the
   // AcceleratedStaticBitmapImage was created on one thread and transferred to
   // another thread, and the original thread gone out of scope, and that we need
   // to clear the resouces associated with that AcceleratedStaticBitmapImage on
   // the original thread.
-  std::unique_ptr<WebTaskRunner> m_textureThreadTaskRunner;
+  RefPtr<WebTaskRunner> m_textureThreadTaskRunner;
 };
 
 }  // namespace blink
 
 #endif  // TextureHolder_h