Making Mandoline apps notice when all the objects they vended are gone so that it can terminate.

components/native_viewport/native_viewport_impl.cc

 // 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.
 
 #include "components/native_viewport/native_viewport_impl.h"
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
 #include "base/time/time.h"
 #include "components/gles2/gpu_state.h"
 #include "components/native_viewport/platform_viewport_headless.h"
 #include "mojo/application/public/cpp/interface_factory.h"
 #include "mojo/converters/geometry/geometry_type_converters.h"
 #include "ui/events/event.h"
 
 namespace native_viewport {
 
 NativeViewportImpl::NativeViewportImpl(
     bool is_headless,
     const scoped_refptr<gles2::GpuState>& gpu_state,
-    mojo::InterfaceRequest<mojo::NativeViewport> request)
+    mojo::InterfaceRequest<mojo::NativeViewport> request,
+    scoped_ptr<mojo::AppRefCount> app_refcount)
     : is_headless_(is_headless),
+      app_refcount_(app_refcount.Pass()),
       context_provider_(new OnscreenContextProvider(gpu_state)),
       sent_metrics_(false),
       metrics_(mojo::ViewportMetrics::New()),
       binding_(this, request.Pass()),
       weak_factory_(this) {
   binding_.set_error_handler(this);
 }
 
 NativeViewportImpl::~NativeViewportImpl() {
   // Destroy before |platform_viewport_| because this will destroy
@@ skipping 126 matching lines @@
 void NativeViewportImpl::OnConnectionError() {
   binding_.set_error_handler(nullptr);
   delete this;
 }
 
 void NativeViewportImpl::AckEvent(int32 pointer_id) {
   pointers_waiting_on_ack_.erase(pointer_id);
 }
 
 }  // namespace native_viewport