build(UWP): fix avformat patch not applying correctly in UWP build

- The git apply command doesn't like the formatting in patch:
  0004-avformat-fix-find_stream_info-not-considering-extradata.patch.
  So it can be reformatted and placed in the ffmpeg-upw.patch file.

Change-Id: If71d3b16bb4ccf23fb47639f10870d390f7784e0
Tuleap: #790

contrib/src/ffmpeg/fetch_and_patch.bat

@@ -34,8 +34,4 @@ if %USE_CACHE%==1 (
 del %FFMPEG_VERSION%.tar && del %FFMPEG_VERSION%.tar.gz && del pax_global_header
 rename FFmpeg-%FFMPEG_VERSION% ffmpeg
 
-cd ffmpeg
-
-git apply --reject --whitespace=fix %SRC%\ffmpeg\0004-avformat-fix-find_stream_info-not-considering-extradata.patch
-
 cd %SRC%
\ No newline at end of file

contrib/src/ffmpeg/ffmpeg-uwp.patch

@@ -72,6 +72,17 @@
          popd
  
      fi
+--- a/ffmpeg/libavformat/utils.c
++++ b/ffmpeg/libavformat/utils.c
+@@ -3432,7 +3432,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
+                     break;
+             }
+             if (st->parser && st->parser->parser->split &&
+-                !st->codecpar->extradata)
++                !st->internal->avctx->extradata)
+                 break;
+             if (st->first_dts == AV_NOPTS_VALUE &&
+                 !(ic->iformat->flags & AVFMT_NOTIMESTAMPS) &&
 -- 
 2.8.1.windows.1