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

content/browser/renderer_host/media/video_capture_host.cc

Index: content/browser/renderer_host/media/video_capture_host.cc
===================================================================
--- content/browser/renderer_host/media/video_capture_host.cc	(revision 137680)
+++ content/browser/renderer_host/media/video_capture_host.cc	(working copy)
@@ -104,6 +104,12 @@
                  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,
@@ -143,6 +149,19 @@
   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,