Adding 2 functions to the Skia API

I need wrappers for both SkOrderedReadBuffer and SkOrderedWriteBuffer inside Chromium in order to do the IPC serialization of Skia SkImageFilter objects.

See https://codereview.chromium.org/21271002/

BUG=
R=djsollen@google.com, scroggo@google.com, reed@google.com

Author: sugoi@chromium.org

Review URL: https://chromiumcodereview.appspot.com/22591002

git-svn-id: http://skia.googlecode.com/svn/trunk@10642 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gyp/core.gypi b/gyp/core.gypi
index 5c3fdf5..d3d998e 100644
--- a/gyp/core.gypi
+++ b/gyp/core.gypi
@@ -87,6 +87,7 @@
         '<(skia_src_path)/core/SkFilterShader.cpp',
         '<(skia_src_path)/core/SkFlattenable.cpp',
         '<(skia_src_path)/core/SkFlattenableBuffers.cpp',
+        '<(skia_src_path)/core/SkFlattenableSerialization.cpp',
         '<(skia_src_path)/core/SkFloat.cpp',
         '<(skia_src_path)/core/SkFloat.h',
         '<(skia_src_path)/core/SkFloatBits.cpp',
@@ -235,6 +236,7 @@
         '<(skia_include_path)/core/SkError.h',
         '<(skia_include_path)/core/SkFixed.h',
         '<(skia_include_path)/core/SkFlattenable.h',
+        '<(skia_include_path)/core/SkFlattenableSerialization.h',
         '<(skia_include_path)/core/SkFloatBits.h',
         '<(skia_include_path)/core/SkFloatingPoint.h',
         '<(skia_include_path)/core/SkFontHost.h',