Rename GrAccelData to SkLayerInfo and move it to src/core

Review URL: https://codereview.chromium.org/719133002
diff --git a/gyp/core.gypi b/gyp/core.gypi
index 120a635..abd4a5c 100644
--- a/gyp/core.gypi
+++ b/gyp/core.gypi
@@ -105,6 +105,8 @@
         '<(skia_src_path)/core/SkImageFilter.cpp',
         '<(skia_src_path)/core/SkImageInfo.cpp',
         '<(skia_src_path)/core/SkImageGenerator.cpp',
+        '<(skia_src_path)/core/SkLayerInfo.h',
+        '<(skia_src_path)/core/SkLayerInfo.cpp',
         '<(skia_src_path)/core/SkLocalMatrixShader.cpp',
         '<(skia_src_path)/core/SkLineClipper.cpp',
         '<(skia_src_path)/core/SkMallocPixelRef.cpp',