Change rtc::VideoSinkWants to have target and a max pixel count

webrtc/media/base/videoadapter.h

Index: webrtc/media/base/videoadapter.h
diff --git a/webrtc/media/base/videoadapter.h b/webrtc/media/base/videoadapter.h
index 553c08577490c667a75a36b783a49c502eae09e8..e011411788102e1b441c38e97d6c41a39fe398e5 100644
--- a/webrtc/media/base/videoadapter.h
+++ b/webrtc/media/base/videoadapter.h
@@ -48,11 +48,13 @@ class VideoAdapter {
   // 720x1280 is requested.
   void OnOutputFormatRequest(const VideoFormat& format);
 
-  // Requests the output frame size from |AdaptFrameResolution| to not have
-  // more than |max_pixel_count| pixels and have "one step" up more pixels than
-  // max_pixel_count_step_up.
-  void OnResolutionRequest(rtc::Optional<int> max_pixel_count,
-                           rtc::Optional<int> max_pixel_count_step_up);
+  // Requests the output frame size from |AdaptFrameResolution| to have as close
+  // as possible to |target_pixel_count|, but no more than |max_pixel_count|
+  // pixels. If |target_pixel_count| is not set, treat it as being equal to
+  // |max_pixel_count|. If |max_pixel_count| is not set, treat is as being the
+  // highest resolution available.
+  void OnResolutionRequest(rtc::Optional<int> target_pixel_count,
+                           rtc::Optional<int> max_pixel_count);

[kthelgason, 2017/02/06 12:13:20]

Maybe we should use this opportunity and change these arguments to just const
int*?

From the rtc::Optional docstring:
When you want to pass a value of a
type T that can fail to be there, const T* is almost always both fastest and
cleanest. (If you're *sure* that the the caller will always already have an
Optional<T>, const Optional<T>& is slightly faster than const T*, but this is a
micro-optimization. In general, stick to const T*.)

[sprang_webrtc, 2017/02/06 13:18:07]

Since we're always gonna have an rtc::Optional in the sink wants, I think we
should stick to that.
I will however change this method to accept const rtc::Optional<int>& instead.
Didn't even notice it wasn't already so.

 
  private:
   // Determine if frame should be dropped based on input fps and requested fps.
@@ -73,8 +75,8 @@ class VideoAdapter {
   // OnResolutionRequest respectively.
   // The adapted output format is the minimum of these.
   rtc::Optional<VideoFormat> requested_format_ GUARDED_BY(critical_section_);
+  int resolution_request_target_pixel_count_ GUARDED_BY(critical_section_);
   int resolution_request_max_pixel_count_ GUARDED_BY(critical_section_);
-  bool step_up_ GUARDED_BY(critical_section_);
 
   // The critical section to protect the above variables.
   rtc::CriticalSection critical_section_;