Use StrongBinding in NativeViewportImpl instead of manually deleting-on-connection-error.

components/view_manager/native_viewport/native_viewport_impl.h

 // Copyright 2014 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 COMPONENTS_VIEW_MANAGER_NATIVE_VIEWPORT_NATIVE_VIEWPORT_IMPL_H_
 #define COMPONENTS_VIEW_MANAGER_NATIVE_VIEWPORT_NATIVE_VIEWPORT_IMPL_H_
 
 #include <set>
 
 #include "base/macros.h"
@@ skipping 14 matching lines @@
 class Event;
 }
 
 namespace native_viewport {
 
 // A NativeViewportImpl is bound to a message pipe and to a PlatformViewport.
 // The NativeViewportImpl's lifetime ends when either the message pipe is closed
 // or the PlatformViewport informs the NativeViewportImpl that it has been
 // destroyed.
 class NativeViewportImpl : public mojo::NativeViewport,
-                           public PlatformViewport::Delegate,
-                           public mojo::ErrorHandler {
+                           public PlatformViewport::Delegate {
  public:
   NativeViewportImpl(bool is_headless,
                      const scoped_refptr<gles2::GpuState>& gpu_state,
                      mojo::InterfaceRequest<mojo::NativeViewport> request,
                      scoped_ptr<mojo::AppRefCount> app_refcount);
   ~NativeViewportImpl() override;
 
   // NativeViewport implementation.
   void Create(mojo::SizePtr size, const CreateCallback& callback) override;
   void RequestMetrics(const RequestMetricsCallback& callback) override;
   void Show() override;
   void Hide() override;
   void Close() override;
   void SetSize(mojo::SizePtr size) override;
   void GetContextProvider(
       mojo::InterfaceRequest<mojo::ContextProvider> request) override;
   void SetEventDispatcher(
       mojo::NativeViewportEventDispatcherPtr dispatcher) override;
 
   // PlatformViewport::Delegate implementation.
   void OnMetricsChanged(mojo::ViewportMetricsPtr metrics) override;
   void OnAcceleratedWidgetAvailable(gfx::AcceleratedWidget widget,
                                     float device_pixel_ratio) override;
   void OnAcceleratedWidgetDestroyed() override;
   bool OnEvent(mojo::EventPtr event) override;
   void OnDestroyed() override;
 
-  // mojo::ErrorHandler implementation.
-  void OnConnectionError() override;
-
  private:
   // Callback when the dispatcher has processed a message we're waiting on
   // an ack from. |pointer_id| identifies the pointer the message was associated
   // with.
   void AckEvent(int32 pointer_id);
 
   bool is_headless_;
   scoped_ptr<mojo::AppRefCount> app_refcount_;
   scoped_ptr<PlatformViewport> platform_viewport_;
   scoped_ptr<OnscreenContextProvider> context_provider_;
   bool sent_metrics_;
   mojo::ViewportMetricsPtr metrics_;
   CreateCallback create_callback_;
   RequestMetricsCallback metrics_callback_;
   mojo::NativeViewportEventDispatcherPtr event_dispatcher_;
-  mojo::Binding<mojo::NativeViewport> binding_;
+  mojo::StrongBinding<mojo::NativeViewport> binding_;
 
   // Set of pointer_ids we've sent a move to and are waiting on an ack.
   std::set<int32> pointers_waiting_on_ack_;
 
   base::WeakPtrFactory<NativeViewportImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeViewportImpl);
 };
 
 }  // namespace native_viewport
 
 #endif  // COMPONENTS_VIEW_MANAGER_NATIVE_VIEWPORT_NATIVE_VIEWPORT_IMPL_H_