Move direct use of VideoCapturer::VideoAdapter to VideoSinkWants.

webrtc/media/base/videobroadcaster.cc

Index: webrtc/media/base/videobroadcaster.cc
diff --git a/webrtc/media/base/videobroadcaster.cc b/webrtc/media/base/videobroadcaster.cc
index e369ee07c632480404080415271572d593c87f06..12ba22685ca15bb633515d637f828ee915efb369 100644
--- a/webrtc/media/base/videobroadcaster.cc
+++ b/webrtc/media/base/videobroadcaster.cc
@@ -33,8 +33,15 @@ void VideoBroadcaster::AddOrUpdateSink(
 
   // Rotation must be applied by the source if one sink wants it.
   current_wants_.rotation_applied = false;
+  current_wants_.max_number_of_pixels = std::numeric_limits<int>::max();

[pthatcher1, 2016/02/17 23:05:56]

Would it make more sense to use an Optional<int>?

[perkj_webrtc, 2016/02/18 13:22:46]

In the interface yes.. but maybe the implementation got worse..

   for (auto& sink_pair : sinks_) {
     current_wants_.rotation_applied |= sink_pair.wants.rotation_applied;
+
+    if (current_wants_.max_number_of_pixels >
+        sink_pair.wants.max_number_of_pixels) {
+      current_wants_.max_number_of_pixels =
+          sink_pair.wants.max_number_of_pixels;
+    }

[pthatcher1, 2016/02/17 23:05:56]

We should document that a local preview sink/renderer will cause the full
resolution to be sent from a track.  So, for this to affect encoding, we need to
make sure that the adapter is attached  down the pipeline after the local
preview is attached to the track.  

I'm not so sure this CL puts the adapter in the right place.

[perkj_webrtc, 2016/02/18 13:22:46]

This is not intended to change the current behavior or move the adapter. ie -
adaptation affect all sinks - including local preview. 
This selects max_number_of_pixels based on the the sink with lowest
requirements.

   }
 }
 
@@ -63,6 +70,8 @@ VideoSinkWants VideoBroadcaster::wants() const {
 
 void VideoBroadcaster::OnFrame(const cricket::VideoFrame& frame) {
   RTC_DCHECK(thread_checker_.CalledOnValidThread());
+  width_ = frame.GetWidth();
+  height_ = frame.GetHeight();
   for (auto& sink_pair : sinks_) {
     sink_pair.sink->OnFrame(frame);
   }