Change VCMFrameBuffer and VCMEncodedFrame to use rotation from base class EncodedImage.

webrtc/modules/video_coding/frame_buffer.cc

Index: webrtc/modules/video_coding/frame_buffer.cc
diff --git a/webrtc/modules/video_coding/frame_buffer.cc b/webrtc/modules/video_coding/frame_buffer.cc
index 61db0d12325059afe4bf906677c4d7e5d39be434..1c7301f933c44f48a7b9933b585f7947eade7c46 100644
--- a/webrtc/modules/video_coding/frame_buffer.cc
+++ b/webrtc/modules/video_coding/frame_buffer.cc
@@ -153,7 +153,7 @@ VCMFrameBufferEnum VCMFrameBuffer::InsertPacket(
   // (HEVC)).
   if (packet.markerBit) {
     RTC_DCHECK(!_rotation_set);
-    _rotation = packet.video_header.rotation;
+    rotation_ = packet.video_header.rotation;
     _rotation_set = true;
   }