Prepare VideoProcessor for async simulcast support.

* Add support for SimulcastEncoderAdapter wrapping of encoder.
* Store input frame timestamps out-of-band, so we don't need to keep
  a raw VideoFrame around just for it's timestamp.
* Store current frame rate in |framerate_fps_|, instead of in
  codec settings struct.
* Add some comments and reorder some data members.
* Explicitly include VideoBitrateAllocator.
* Change type of |input_frames_|, to avoid one layer of indirection.
* Move VideoProcessor::CalculateFrameQuality to anonymous namespace.

This change should have no functional implications.

Bug: webrtc:8448
Change-Id: I10c140eeda750d9bd37bfb6cb1e8acb401fb91d3
Reviewed-on: https://webrtc-review.googlesource.com/60520
Commit-Queue: Rasmus Brandt <brandtr@webrtc.org>
Reviewed-by: Sergey Silkin <ssilkin@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22346}
diff --git a/modules/video_coding/DEPS b/modules/video_coding/DEPS
index b9c8dac..98242be 100644
--- a/modules/video_coding/DEPS
+++ b/modules/video_coding/DEPS
@@ -12,7 +12,7 @@
   "android_codec_factory_helper\.cc": [
     "+base/android",
   ],
-  "test_config.cc": [
+  ".*test.*\.cc": [
      "+media/base",
      "+media/engine",
   ],