Removed custom FFmpegLock. Removed ffmpeg headers from third_party/ffmpeg/include.

DEPS

Index: DEPS
diff --git a/DEPS b/DEPS
index 5b5cbf447f612639db9cc700b5fd6f6dba4c5879..35622c422aae4e57ef42e2b3a07f6ed7c9465857 100644
--- a/DEPS
+++ b/DEPS
@@ -104,6 +104,10 @@ deps = {
 
   "src/third_party/swig/Lib":
     "/trunk/deps/third_party/swig/Lib@" + Var("swig_revision"),
+
+  "src/third_party/ffmpeg/source/patched-ffmpeg-mt":
+    "/trunk/deps/third_party/ffmpeg/patched-ffmpeg-mt@" +
+    Var("ffmpeg_revision"),
 }
 
 
@@ -165,9 +169,6 @@ deps_os = {
     # TODO(ajwong): Move this into the OS-independent block.
     "src/third_party/yasm/source/patched-yasm":
       "/trunk/deps/third_party/yasm/patched-yasm@29937",
-    "src/third_party/ffmpeg/source/patched-ffmpeg-mt":
-      "/trunk/deps/third_party/ffmpeg/patched-ffmpeg-mt@" +
-      Var("ffmpeg_revision"),
 
     "src/third_party/swig/mac":
       "/trunk/deps/third_party/swig/mac@" + Var("swig_revision"),
@@ -183,9 +184,6 @@ deps_os = {
     # TODO(ajwong): Move this into the OS-independent block.
     "src/third_party/yasm/source/patched-yasm":
       "/trunk/deps/third_party/yasm/patched-yasm@29937",
-    "src/third_party/ffmpeg/source/patched-ffmpeg-mt":
-      "/trunk/deps/third_party/ffmpeg/patched-ffmpeg-mt@" +
-      Var("ffmpeg_revision"),
 
     "src/third_party/swig/linux":
       "/trunk/deps/third_party/swig/linux@" + Var("swig_revision"),