Eliminate video capture thread in renderer

The main motivation of this change is to remove the video capture thread
in the renderer. All users of a video capture device already handles the
video frame on their thread. There is no need to call the clients with
an additional thread.

Summary of this change:
* Video capture thread eliminated
  VideoCaptureImpl now runs on the IO thread. Clients are called on the
  IO thread.
* Simplified VideoCaptureImplManager
  We still need to keep this object for the purpose of sharing a
  VideoCaptureImpl object with multiple clients. It should own these
  objects and maintain the usage count. A couple clean up items are done
  on this class:
  * It doesn't own the video capture thread now.
  * It is now a render thread only object.
  * It maintains refcount of a VideoCaptureImpl explicitly.
  * It is no longer refcounted.
  * Clients access it through RenderThreadImpl. Which ensures usage is
    on the render thread.
* New VideoCaptureHandle class
  Object of this class is returned by VideoCaptureImplManager to give
  access to a media::VideoCapture object. It is purely a wrapper and
  helps to do refcounting on the render thread.

Testing:
Added unit tests for VideoCaptureImplManager to test refcounting.
Also updated unit test for VideoCaptureImpl due to the threading
changes.

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=244074

Review URL: https://codereview.chromium.org/120893002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244687 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 62 insertions, 136 deletions

diff --git a/content/renderer/media/video_capture_impl_unittest.cc b/content/renderer/media/video_capture_impl_unittest.cc
index 713b3a0..2c9c75a 100644
--- a/content/renderer/media/video_capture_impl_unittest.cc
+++ b/content/renderer/media/video_capture_impl_unittest.cc
@@ -3,15 +3,18 @@
 // found in the LICENSE file.
 
 #include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
 #include "content/child/child_process.h"
 #include "content/common/media/video_capture_messages.h"
 #include "content/renderer/media/video_capture_impl.h"
+#include "media/base/bind_to_current_loop.h"
+#include "media/video/capture/mock_video_capture_event_handler.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using ::testing::_;
 using ::testing::AtLeast;
-using ::testing::Return;
+using media::MockVideoCaptureEventHandler;
 
 namespace content {
 
@@ -29,36 +32,13 @@ class MockVideoCaptureMessageFilter : public VideoCaptureMessageFilter {
   DISALLOW_COPY_AND_ASSIGN(MockVideoCaptureMessageFilter);
 };
 
-class MockVideoCaptureClient : public media::VideoCapture::EventHandler {
- public:
-  MockVideoCaptureClient() {}
-  virtual ~MockVideoCaptureClient() {}
-
-  // 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(OnFrameReady,
-               void(media::VideoCapture* capture,
-                    const scoped_refptr<media::VideoFrame>& frame));
-  MOCK_METHOD2(OnDeviceInfoReceived,
-               void(media::VideoCapture* capture,
-                    const media::VideoCaptureFormat& device_info));
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(MockVideoCaptureClient);
-};
-
 class VideoCaptureImplTest : public ::testing::Test {
  public:
   class MockVideoCaptureImpl : public VideoCaptureImpl {
    public:
     MockVideoCaptureImpl(const media::VideoCaptureSessionId id,
-                         scoped_refptr<base::MessageLoopProxy> ml_proxy,
                          VideoCaptureMessageFilter* filter)
-        : VideoCaptureImpl(id, ml_proxy.get(), filter) {}
+        : VideoCaptureImpl(id, filter) {}
     virtual ~MockVideoCaptureImpl() {}
 
     // Override Send() to mimic device to send events.
@@ -102,15 +82,13 @@ class VideoCaptureImplTest : public ::testing::Test {
     params_large_.requested_format = media::VideoCaptureFormat(
         gfx::Size(320, 240), 30, media::PIXEL_FORMAT_I420);
 
-    message_loop_.reset(new base::MessageLoop(base::MessageLoop::TYPE_IO));
-    message_loop_proxy_ = base::MessageLoopProxy::current().get();
     child_process_.reset(new ChildProcess());
 
     message_filter_ = new MockVideoCaptureMessageFilter;
     session_id_ = 1;
 
     video_capture_impl_ = new MockVideoCaptureImpl(
-        session_id_, message_loop_proxy_, message_filter_.get());
+        session_id_, message_filter_.get());
 
     video_capture_impl_->device_id_ = 2;
   }
@@ -120,8 +98,8 @@ class VideoCaptureImplTest : public ::testing::Test {
   }
 
  protected:
-  scoped_ptr<base::MessageLoop> message_loop_;
-  scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
+  base::MessageLoop message_loop_;
+  base::RunLoop run_loop_;
   scoped_ptr<ChildProcess> child_process_;
   scoped_refptr<MockVideoCaptureMessageFilter> message_filter_;
   media::VideoCaptureSessionId session_id_;
@@ -135,141 +113,89 @@ class VideoCaptureImplTest : public ::testing::Test {
 
 TEST_F(VideoCaptureImplTest, Simple) {
   // Execute SetCapture() and StopCapture() for one client.
-  scoped_ptr<MockVideoCaptureClient> client(new MockVideoCaptureClient);
+  scoped_ptr<MockVideoCaptureEventHandler> client(
+      new MockVideoCaptureEventHandler);
 
-  EXPECT_CALL(*client, OnStarted(_))
-      .WillOnce(Return());
+  EXPECT_CALL(*client, OnStarted(_));
+  EXPECT_CALL(*client, OnStopped(_));
+  EXPECT_CALL(*client, OnRemoved(_));
 
   video_capture_impl_->StartCapture(client.get(), params_small_);
-  message_loop_->RunUntilIdle();
-
-  EXPECT_CALL(*client, OnStopped(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client, OnRemoved(_))
-      .WillOnce(Return());
-
   video_capture_impl_->StopCapture(client.get());
-  message_loop_->RunUntilIdle();
+  video_capture_impl_->DeInit(
+      media::BindToCurrentLoop(run_loop_.QuitClosure()));
+  run_loop_.Run();
 }
 
 TEST_F(VideoCaptureImplTest, TwoClientsInSequence) {
   // Execute SetCapture() and StopCapture() for 2 clients in sequence.
-  scoped_ptr<MockVideoCaptureClient> client(new MockVideoCaptureClient);
-
-  EXPECT_CALL(*client, OnStarted(_))
-      .WillOnce(Return());
-
-  video_capture_impl_->StartCapture(client.get(), params_small_);
-  message_loop_->RunUntilIdle();
+  scoped_ptr<MockVideoCaptureEventHandler> client1(
+      new MockVideoCaptureEventHandler);
+  scoped_ptr<MockVideoCaptureEventHandler> client2(
+      new MockVideoCaptureEventHandler);
+
+  EXPECT_CALL(*client1, OnStarted(_));
+  EXPECT_CALL(*client1, OnStopped(_));
+  EXPECT_CALL(*client1, OnRemoved(_));
+  EXPECT_CALL(*client2, OnStarted(_));
+  EXPECT_CALL(*client2, OnStopped(_));
+  EXPECT_CALL(*client2, OnRemoved(_));
 
-  EXPECT_CALL(*client, OnStopped(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client, OnRemoved(_))
-      .WillOnce(Return());
-
-  video_capture_impl_->StopCapture(client.get());
-  message_loop_->RunUntilIdle();
-
-  EXPECT_CALL(*client, OnStarted(_))
-      .WillOnce(Return());
-
-  video_capture_impl_->StartCapture(client.get(), params_small_);
-  message_loop_->RunUntilIdle();
-
-  EXPECT_CALL(*client, OnStopped(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client, OnRemoved(_))
-      .WillOnce(Return());
-
-  video_capture_impl_->StopCapture(client.get());
-  message_loop_->RunUntilIdle();
+  video_capture_impl_->StartCapture(client1.get(), params_small_);
+  video_capture_impl_->StopCapture(client1.get());
+  video_capture_impl_->StartCapture(client2.get(), params_small_);
+  video_capture_impl_->StopCapture(client2.get());
+  video_capture_impl_->DeInit(
+      media::BindToCurrentLoop(run_loop_.QuitClosure()));
+  run_loop_.Run();
 }
 
 TEST_F(VideoCaptureImplTest, LargeAndSmall) {
   // Execute SetCapture() and StopCapture() for 2 clients simultaneously.
   // The large client starts first and stops first.
-  scoped_ptr<MockVideoCaptureClient> client_small(new MockVideoCaptureClient);
-  scoped_ptr<MockVideoCaptureClient> client_large(new MockVideoCaptureClient);
-
-  EXPECT_CALL(*client_large, OnStarted(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client_small, OnStarted(_))
-      .WillOnce(Return());
+  scoped_ptr<MockVideoCaptureEventHandler> client_small(
+      new MockVideoCaptureEventHandler);
+  scoped_ptr<MockVideoCaptureEventHandler> client_large(
+      new MockVideoCaptureEventHandler);
+
+  EXPECT_CALL(*client_large, OnStarted(_));
+  EXPECT_CALL(*client_small, OnStarted(_));
+  EXPECT_CALL(*client_large, OnStopped(_));
+  EXPECT_CALL(*client_large, OnRemoved(_));
+  EXPECT_CALL(*client_small, OnStopped(_));
+  EXPECT_CALL(*client_small, OnRemoved(_));
 
   video_capture_impl_->StartCapture(client_large.get(), params_large_);
   video_capture_impl_->StartCapture(client_small.get(), params_small_);
-  message_loop_->RunUntilIdle();
-
-  EXPECT_CALL(*client_large, OnStopped(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client_large, OnRemoved(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client_small, OnStopped(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client_small, OnRemoved(_))
-      .WillOnce(Return());
-
   video_capture_impl_->StopCapture(client_large.get());
   video_capture_impl_->StopCapture(client_small.get());
-  message_loop_->RunUntilIdle();
+  video_capture_impl_->DeInit(
+      media::BindToCurrentLoop(run_loop_.QuitClosure()));
+  run_loop_.Run();
 }
 
 TEST_F(VideoCaptureImplTest, SmallAndLarge) {
   // Execute SetCapture() and StopCapture() for 2 clients simultaneously.
   // The small client starts first and stops first.
-  scoped_ptr<MockVideoCaptureClient> client_small(new MockVideoCaptureClient);
-  scoped_ptr<MockVideoCaptureClient> client_large(new MockVideoCaptureClient);
-
-  EXPECT_CALL(*client_large, OnStarted(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client_small, OnStarted(_))
-      .WillOnce(Return());
+  scoped_ptr<MockVideoCaptureEventHandler> client_small(
+      new MockVideoCaptureEventHandler);
+  scoped_ptr<MockVideoCaptureEventHandler> client_large(
+      new MockVideoCaptureEventHandler);
+
+  EXPECT_CALL(*client_small, OnStarted(_));
+  EXPECT_CALL(*client_large, OnStarted(_));
+  EXPECT_CALL(*client_small, OnStopped(_));
+  EXPECT_CALL(*client_small, OnRemoved(_));
+  EXPECT_CALL(*client_large, OnStopped(_));
+  EXPECT_CALL(*client_large, OnRemoved(_));
 
   video_capture_impl_->StartCapture(client_small.get(), params_small_);
   video_capture_impl_->StartCapture(client_large.get(), params_large_);
-  message_loop_->RunUntilIdle();
-
-  EXPECT_CALL(*client_large, OnStopped(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client_large, OnRemoved(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client_small, OnStopped(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client_small, OnRemoved(_))
-      .WillOnce(Return());
-
   video_capture_impl_->StopCapture(client_small.get());
   video_capture_impl_->StopCapture(client_large.get());
-  message_loop_->RunUntilIdle();
-}
-
-TEST_F(VideoCaptureImplTest, TwoClientsWithSameSize) {
-  // Execute SetCapture() and StopCapture() for 2 clients simultaneously.
-  // The client1 starts first and stops first.
-  scoped_ptr<MockVideoCaptureClient> client1(new MockVideoCaptureClient);
-  scoped_ptr<MockVideoCaptureClient> client2(new MockVideoCaptureClient);
-
-  EXPECT_CALL(*client1, OnStarted(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client2, OnStarted(_))
-      .WillOnce(Return());
-
-  video_capture_impl_->StartCapture(client1.get(), params_small_);
-  video_capture_impl_->StartCapture(client2.get(), params_small_);
-  message_loop_->RunUntilIdle();
-
-  EXPECT_CALL(*client1, OnStopped(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client1, OnRemoved(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client2, OnStopped(_))
-      .WillOnce(Return());
-  EXPECT_CALL(*client2, OnRemoved(_))
-      .WillOnce(Return());
-
-  video_capture_impl_->StopCapture(client1.get());
-  video_capture_impl_->StopCapture(client2.get());
-  message_loop_->RunUntilIdle();
+  video_capture_impl_->DeInit(
+      media::BindToCurrentLoop(run_loop_.QuitClosure()));
+  run_loop_.Run();
 }
 
 }  // namespace content