Revert 150545 - roll skia to 5000

Review URL: https://chromiumcodereview.appspot.com/10824211
broke win build

TBR=reed@google.com
Review URL: https://chromiumcodereview.appspot.com/10823231

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@150548 0039d316-1c4b-4281-b951-d872f2087c98

DEPS

@@ -29,7 +29,7 @@ vars = {
   "ffmpeg_hash": "2079ffae30f8da6c6eed985cce00e04c31b40888",
 
   "sfntly_revision": "134",
-  "skia_revision": "5000",
+  "skia_revision": "4991",
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and V8 without interference from each other.

skia/skia.gyp

@@ -180,7 +180,6 @@
         '../third_party/skia/src/core/SkAlphaRuns.cpp',
         '../third_party/skia/src/core/SkAntiRun.h',
         '../third_party/skia/src/core/SkBitmap.cpp',
-        '../third_party/skia/src/core/SkBitmapHeap.cpp',
         '../third_party/skia/src/core/SkBitmapProcShader.cpp',
         '../third_party/skia/src/core/SkBitmapProcShader.h',
         '../third_party/skia/src/core/SkBitmapProcState.cpp',