Delete unused and almost unused frame-related methods.

webrtc/modules/video_coding/video_sender.cc

Index: webrtc/modules/video_coding/video_sender.cc
diff --git a/webrtc/modules/video_coding/video_sender.cc b/webrtc/modules/video_coding/video_sender.cc
index b9c5ea547a40865cc18e1eb49c657504c22c31cc..73d4f0b7beaf6aaf8231943f8546a8860bd2e90b 100644
--- a/webrtc/modules/video_coding/video_sender.cc
+++ b/webrtc/modules/video_coding/video_sender.cc
@@ -288,9 +288,17 @@ int32_t VideoSender::AddVideoFrame(const VideoFrame& videoFrame,
       !_encoder->SupportsNativeHandle()) {
     // This module only supports software encoding.
     // TODO(pbos): Offload conversion from the encoder thread.
-    converted_frame = converted_frame.ConvertNativeToI420Frame();
-    RTC_CHECK(!converted_frame.IsZeroSize())
+    // TODO(nisse): Do we need to propagate the meta data?

[pbos-webrtc, 2016/06/14 13:47:05]

what meta data? I have no idea what this comment means.

[nisse-webrtc, 2016/06/14 14:32:14]

Frame timestamps and rotation. Does the encoder care about them? Before this cl,
rotation was discarded, propagating it below is a change which I'm not 100% sure
is correct.

If you explain it, I'll happily remove the comment.

[pbos-webrtc, 2016/06/14 14:34:15]

It should, timestamp and rotation needs to be forwarded through the encoder. I
think you fixed a bug here.

[nisse-webrtc, 2016/06/15 07:49:20]

I see, deleted the comment. And on second look, I don't think behaviour is
changed here, the old ConvertNativeToI420Frame did copy rotation.

+    rtc::scoped_refptr<VideoFrameBuffer> converted_buffer(
+        converted_frame.video_frame_buffer()->NativeToI420Buffer());
+
+    RTC_CHECK(converted_buffer)
         << "Frame conversion failed, won't be able to encode frame.";
+
+    converted_frame = VideoFrame(converted_buffer,
+                                 converted_frame.timestamp(),
+                                 converted_frame.render_time_ms(),
+                                 converted_frame.rotation());
   }
   int32_t ret =
       _encoder->Encode(converted_frame, codecSpecificInfo, next_frame_types);