handle the case when device is closed before media pipeline is fully initialized.

content/browser/renderer_host/media/video_capture_host.cc

 // Copyright (c) 2012 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 "content/browser/renderer_host/media/video_capture_host.h"
 
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/stl_util.h"
 #include "content/browser/renderer_host/media/media_stream_manager.h"
@@ skipping 86 matching lines @@
 void VideoCaptureHost::OnFrameInfo(const VideoCaptureControllerID& id,
                                    int width,
                                    int height,
                                    int frame_per_second) {
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       base::Bind(&VideoCaptureHost::DoSendFrameInfo,
                  this, id.device_id, width, height, frame_per_second));
 }
 
+void VideoCaptureHost::OnPaused(const VideoCaptureControllerID& id) {
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      base::Bind(&VideoCaptureHost::DoPaused, this, id.device_id));
+}
+
 void VideoCaptureHost::OnReadyToDelete(const VideoCaptureControllerID& id) {
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       base::Bind(&VideoCaptureHost::DoDeleteVideoCaptureController, this, id));
 }
 
 void VideoCaptureHost::DoSendNewBuffer(
     int device_id, base::SharedMemoryHandle handle,
     int length, int buffer_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
@@ skipping 19 matching lines @@
     return;
 
   it->second->state = video_capture::kError;
   Send(new VideoCaptureMsg_StateChanged(device_id,
                                         video_capture::kError));
 
   VideoCaptureController* controller = it->second->controller;
   controller->StopCapture(id, this, false);
 }
 
+void VideoCaptureHost::DoPaused(int device_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  VideoCaptureControllerID id(device_id);
+  EntryMap::iterator it = entries_.find(id);
+  if (it == entries_.end() || it->second->state == video_capture::kPaused)
+    return;
+
+  it->second->state = video_capture::kPaused;
+  Send(new VideoCaptureMsg_StateChanged(device_id,
+                                        video_capture::kPaused));
+}
+
 void VideoCaptureHost::DoSendFrameInfo(int device_id,
                                        int width,
                                        int height,
                                        int frame_per_second) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   media::VideoCaptureParams params;
   params.width = width;
   params.height = height;
   params.frame_per_second = frame_per_second;
@@ skipping 134 matching lines @@
     delete it->second;
     entries_.erase(id);
   }
 }
 
 media_stream::VideoCaptureManager* VideoCaptureHost::GetVideoCaptureManager() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   return media_stream::MediaStreamManager::GetForResourceContext(
       resource_context_, audio_manager_)->video_capture_manager();
 }