ffmpeg delete source folder and use deps to pull in all content....

third_party/ffmpeg/avformat-52.sigs

Index: third_party/ffmpeg/avformat-52.sigs
===================================================================
--- third_party/ffmpeg/avformat-52.sigs	(revision 48686)
+++ third_party/ffmpeg/avformat-52.sigs	(working copy)
@@ -1,13 +0,0 @@
-# Copyright (c) 2009 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-#
-# Functions from avformat used in chromium code.
-
-int av_find_stream_info(AVFormatContext *ic);
-int av_open_input_file(AVFormatContext **ic_ptr, const char *filename, AVInputFormat *fmt, int buf_size, AVFormatParameters *ap);
-void av_close_input_file(AVFormatContext *s);
-int av_read_frame(AVFormatContext *s, AVPacket *pkt);
-int av_register_protocol(URLProtocol *protocol);
-int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags);
-void av_register_all(void);