Add OnRemoved() in VideoCapture::EventHandler API

This is to allow client to know when the event handler can be deleted.

BUG=none
TEST=trybots
Review URL: http://codereview.chromium.org/8037055

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@103016 0039d316-1c4b-4281-b951-d872f2087c98

content/renderer/media/capture_video_decoder.cc

@@ -109,6 +109,10 @@ void CaptureVideoDecoder::OnError(media::VideoCapture* capture,
   NOTIMPLEMENTED();
 }
 
+void CaptureVideoDecoder::OnRemoved(media::VideoCapture* capture) {
+  NOTIMPLEMENTED();
+}
+
 void CaptureVideoDecoder::OnBufferReady(
     media::VideoCapture* capture,
     scoped_refptr<media::VideoCapture::VideoFrameBuffer> buf) {

content/renderer/media/capture_video_decoder.h

@@ -51,6 +51,7 @@ class CaptureVideoDecoder
   virtual void OnStopped(media::VideoCapture* capture) OVERRIDE;
   virtual void OnPaused(media::VideoCapture* capture) OVERRIDE;
   virtual void OnError(media::VideoCapture* capture, int error_code) OVERRIDE;
+  virtual void OnRemoved(media::VideoCapture* capture) OVERRIDE;
   virtual void OnBufferReady(
       media::VideoCapture* capture,
       scoped_refptr<media::VideoCapture::VideoFrameBuffer> buf) OVERRIDE;

content/renderer/media/video_capture_impl.cc

@@ -144,6 +144,7 @@ void VideoCaptureImpl::DoStartCapture(
 
   if (it != pending_clients_.end()) {
     handler->OnError(this, 1);
+    handler->OnRemoved(this);
     return;
   }
 
@@ -157,6 +158,7 @@ void VideoCaptureImpl::DoStartCapture(
        capability.height != current_params_.height)) {
     // Can't have 2 master clients with different resolutions.
     handler->OnError(this, 1);
+    handler->OnRemoved(this);
     return;
   }
 
@@ -219,6 +221,7 @@ void VideoCaptureImpl::DoStopCapture(
   ClientInfo::iterator it = pending_clients_.find(handler);
   if (it != pending_clients_.end()) {
     handler->OnStopped(this);
+    handler->OnRemoved(this);
     pending_clients_.erase(it);
     return;
   }
@@ -227,6 +230,7 @@ void VideoCaptureImpl::DoStopCapture(
     return;
 
   handler->OnStopped(this);
+  handler->OnRemoved(this);
   clients_.erase(handler);
   master_clients_.remove(handler);
 
@@ -368,7 +372,12 @@ void VideoCaptureImpl::DoStateChanged(const media::VideoCapture::State& state) {
            it != clients_.end(); it++) {
         // TODO(wjia): browser process would send error code.
         it->first->OnError(this, 1);
+        it->first->OnRemoved(this);
       }
+      clients_.clear();
+      master_clients_.clear();
+      state_ = kStopped;
+      current_params_.width = current_params_.height = 0;
       break;
     default:
       break;

content/renderer/media/video_capture_impl_unittest.cc

@@ -34,11 +34,12 @@ class MockVideoCaptureClient : public media::VideoCapture::EventHandler {
   MockVideoCaptureClient() {}
   virtual ~MockVideoCaptureClient() {}
 
-  // Filter implementation.
+  // EventHandler implementation.
   MOCK_METHOD1(OnStarted, void(media::VideoCapture* capture));
   MOCK_METHOD1(OnStopped, void(media::VideoCapture* capture));
   MOCK_METHOD1(OnPaused, void(media::VideoCapture* capture));
   MOCK_METHOD2(OnError, void(media::VideoCapture* capture, int error_code));
+  MOCK_METHOD1(OnRemoved, void(media::VideoCapture* capture));
   MOCK_METHOD2(OnBufferReady,
                void(media::VideoCapture* capture,
                     scoped_refptr<media::VideoCapture::VideoFrameBuffer> buf));

content/renderer/media/video_capture_module_impl.cc

@@ -105,6 +105,10 @@ void VideoCaptureModuleImpl::OnError(media::VideoCapture* capture,
   NOTIMPLEMENTED();
 }
 
+void VideoCaptureModuleImpl::OnRemoved(media::VideoCapture* capture) {
+  NOTIMPLEMENTED();
+}
+
 void VideoCaptureModuleImpl::OnBufferReady(
     media::VideoCapture* capture,
     scoped_refptr<media::VideoCapture::VideoFrameBuffer> buf) {

content/renderer/media/video_capture_module_impl.h

@@ -40,6 +40,7 @@ class VideoCaptureModuleImpl
   virtual void OnStopped(media::VideoCapture* capture);
   virtual void OnPaused(media::VideoCapture* capture);
   virtual void OnError(media::VideoCapture* capture, int error_code);
+  virtual void OnRemoved(media::VideoCapture* capture);
   virtual void OnBufferReady(
       media::VideoCapture* capture,
       scoped_refptr<media::VideoCapture::VideoFrameBuffer> buf);

media/video/capture/video_capture.h

@@ -66,6 +66,10 @@ class VideoCapture {
     // Notify client that video capture has hit some error |error_code|.
     virtual void OnError(VideoCapture* capture, int error_code) = 0;
 
+    // Notify client that the client has been removed and no more calls will be
+    // received.
+    virtual void OnRemoved(VideoCapture* capture) = 0;
+
     // Notify client that a buffer is available.
     virtual void OnBufferReady(VideoCapture* capture,
                                scoped_refptr<VideoFrameBuffer> buffer) = 0;
@@ -93,10 +97,12 @@ class VideoCapture {
 
   // Request video capture to start capturing with |capability|.
   // Also register |handler| with video capture for event handling.
+  // |handler| must remain valid until it has received |OnRemoved()|.
   virtual void StartCapture(EventHandler* handler,
                             const VideoCaptureCapability& capability) = 0;
 
   // Request video capture to stop capturing for client |handler|.
+  // |handler| must remain valid until it has received |OnRemoved()|.
   virtual void StopCapture(EventHandler* handler) = 0;
 
   // Feed buffer to video capture when done with it.

media/video/capture/video_capture_proxy.cc

@@ -68,6 +68,10 @@ void VideoCaptureHandlerProxy::OnError(VideoCapture* capture, int error_code) {
       error_code));
 }
 
+void VideoCaptureHandlerProxy::OnRemoved(VideoCapture* capture) {
+  // TODO(vtl): add logic when this event handler is removed.
+}
+
 void VideoCaptureHandlerProxy::OnBufferReady(
     VideoCapture* capture,
     scoped_refptr<VideoCapture::VideoFrameBuffer> buffer) {

media/video/capture/video_capture_proxy.h

@@ -51,6 +51,7 @@ class MEDIA_EXPORT VideoCaptureHandlerProxy
   virtual void OnStopped(VideoCapture* capture) OVERRIDE;
   virtual void OnPaused(VideoCapture* capture) OVERRIDE;
   virtual void OnError(VideoCapture* capture, int error_code) OVERRIDE;
+  virtual void OnRemoved(VideoCapture* capture) OVERRIDE;
   virtual void OnBufferReady(
       VideoCapture* capture,
       scoped_refptr<VideoCapture::VideoFrameBuffer> buffer) OVERRIDE;

webkit/plugins/ppapi/ppb_video_capture_impl.cc

@@ -167,6 +167,10 @@ void PPB_VideoCapture_Impl::OnError(media::VideoCapture* capture,
   ppp_videocapture_->OnError(pp_instance(), pp_resource(), PP_ERROR_FAILED);
 }
 
+void PPB_VideoCapture_Impl::OnRemoved(media::VideoCapture* capture) {
+  // TODO(vtl): add logic when this event handler is removed.
+}
+
 void PPB_VideoCapture_Impl::OnBufferReady(
     media::VideoCapture* capture,
     scoped_refptr<media::VideoCapture::VideoFrameBuffer> buffer) {

webkit/plugins/ppapi/ppb_video_capture_impl.h

@@ -48,6 +48,7 @@ class PPB_VideoCapture_Impl : public ::ppapi::Resource,
   virtual void OnStopped(media::VideoCapture* capture) OVERRIDE;
   virtual void OnPaused(media::VideoCapture* capture) OVERRIDE;
   virtual void OnError(media::VideoCapture* capture, int error_code) OVERRIDE;
+  virtual void OnRemoved(media::VideoCapture* capture) OVERRIDE;
   virtual void OnBufferReady(
       media::VideoCapture* capture,
       scoped_refptr<media::VideoCapture::VideoFrameBuffer> buffer) OVERRIDE;