Properly skip the 'skip' chunk in mpeg4 files.

Change-Id: I6795347f91f24d5379e8dc80a24ae016a9629c9c
related-to-bug: 2901311
diff --git a/media/libstagefright/MPEG4Extractor.cpp b/media/libstagefright/MPEG4Extractor.cpp
index 7cea6298..d937838 100644
--- a/media/libstagefright/MPEG4Extractor.cpp
+++ b/media/libstagefright/MPEG4Extractor.cpp
@@ -492,7 +492,6 @@
         case FOURCC('m', 'o', 'o', 'f'):
         case FOURCC('t', 'r', 'a', 'f'):
         case FOURCC('m', 'f', 'r', 'a'):
-        case FOURCC('s', 'k', 'i' ,'p'):
         case FOURCC('u', 'd', 't', 'a'):
         case FOURCC('i', 'l', 's', 't'):
         {