Created VideoFramePool to avoid unnecessary VideoFrame alloc/free.

media/filters/vpx_video_decoder.h

Index: media/filters/vpx_video_decoder.h
diff --git a/media/filters/vpx_video_decoder.h b/media/filters/vpx_video_decoder.h
index 680337ae532b0aca6c243587ee07e1ae492552af..cc02e89aad0b57027818b3f1702c8f8d5e9f2669 100644
--- a/media/filters/vpx_video_decoder.h
+++ b/media/filters/vpx_video_decoder.h
@@ -11,6 +11,7 @@
 #include "media/base/video_decoder.h"
 #include "media/base/video_decoder_config.h"
 #include "media/base/video_frame.h"
+#include "media/base/video_frame_pool.h"
 
 struct vpx_codec_ctx;
 struct vpx_image;
@@ -80,6 +81,8 @@ class MEDIA_EXPORT VpxVideoDecoder : public VideoDecoder {
   vpx_codec_ctx* vpx_codec_;
   vpx_codec_ctx* vpx_codec_alpha_;
 
+  VideoFramePool frame_pool_;
+
   DISALLOW_COPY_AND_ASSIGN(VpxVideoDecoder);
 };