Added image pattern comparison logic for test interface and fixture.

remoting/test/test_video_renderer.h

Index: remoting/test/test_video_renderer.h
diff --git a/remoting/test/test_video_renderer.h b/remoting/test/test_video_renderer.h
index b9a84f7ff697e02520984054ba5366c7b7fb9b7b..bb87b72e2210995693d74890f31ed2b82456491b 100644
--- a/remoting/test/test_video_renderer.h
+++ b/remoting/test/test_video_renderer.h
@@ -23,8 +23,6 @@ class DesktopFrame;
 class DesktopRect;
 }
 
-typedef uint32 RgbaColor;
-
 namespace remoting {
 namespace test {
 
@@ -49,8 +47,8 @@ class TestVideoRenderer : public VideoRenderer, public protocol::VideoStub {
   // Initialize a decoder to decode video packets.
   void SetCodecForDecoding(const protocol::ChannelConfig::Codec codec);
 
-  // Returns a copy of the current buffer.
-  scoped_ptr<webrtc::DesktopFrame> GetBufferForTest() const;
+  // Returns a copy of the current frame.
+  scoped_ptr<webrtc::DesktopFrame> GetCurrentFrameForTest() const;
 
   // Gets a weak pointer for this object.
   base::WeakPtr<TestVideoRenderer> GetWeakPtr() {
@@ -61,7 +59,7 @@ class TestVideoRenderer : public VideoRenderer, public protocol::VideoStub {
   // when the pattern is matched.
   void SetImagePatternAndMatchedCallback(

[Sergey Ulanov, 2015/07/13 19:42:18]

Maybe call this differently to reflect actual behavior. 
 1. there is no pattern to match, it just compares average color
 2. the name implies that it just sets the callback, while it also sets expected
color and rect.

Maybe something like ExpectAverageColorInRect() might be better.

BTW, not for this CL: it would be a good idea to move matching code out of this
class, to make it possible to use different matching algorithms without any
changes using the same TestVideoRenderer. So PatternMatcher would be just a
listener for incoming video frames and calling the callback, and then the
threading logic in TestVideoRenderer would be isolated from pattern matching.
That would also make your unittests simpler.

[liaoyuke, 2015/07/13 20:43:18]

Totally agree with your idea to move matching code out, and I will refactor the
code when I got chance.

[liaoyuke, 2015/07/13 20:43:18]

Done.

       const webrtc::DesktopRect& expected_rect,
-      const RgbaColor& expected_color,
+      uint32_t expected_color,

[Sergey Ulanov, 2015/07/13 19:42:18]

call this expected_average_color and document it in the comments. The comment
says "pattern is matched" while there is no actual pattern matching happening.

[liaoyuke, 2015/07/13 20:43:19]

Done.

       const base::Closure& image_pattern_matched_callback);
 
  private: