Add a buffered SkStream class.

This is used by Android to buffer an input stream which may not
otherwise be able to rewind.

Add a test for the new class.

R=bungeman@google.com, mtklein@google.com, reed@google.com

Review URL: https://codereview.chromium.org/23717055

git-svn-id: http://skia.googlecode.com/svn/trunk@11488 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gyp/utils.gyp b/gyp/utils.gyp
index d3bac16..1725910 100644
--- a/gyp/utils.gyp
+++ b/gyp/utils.gyp
@@ -34,6 +34,7 @@
         '../src/utils/SkThreadPool.cpp',
 
         '../include/utils/SkBoundaryPatch.h',
+        '../include/utils/SkFrontBufferedStream.h',
         '../include/utils/SkCamera.h',
         '../include/utils/SkCanvasStateUtils.h',
         '../include/utils/SkCubicInterval.h',
@@ -65,6 +66,7 @@
         '../src/utils/SkBitSet.cpp',
         '../src/utils/SkBitSet.h',
         '../src/utils/SkBoundaryPatch.cpp',
+        '../src/utils/SkFrontBufferedStream.cpp',
         '../src/utils/SkCamera.cpp',
         '../src/utils/SkCanvasStack.h',
         '../src/utils/SkCanvasStack.cpp',