Rename SkCanvasDrawable to SkDrawable, and make public

 (patchset #2 id:20001 of https://codereview.chromium.org/903993002/)"

This reverts commit c4e87724920222a218f31b22612efc5b1ec0ed6c.

BUG=skia:
TBR=
NOTREECHECKS=True

Review URL: https://codereview.chromium.org/898343004
diff --git a/gyp/core.gypi b/gyp/core.gypi
index e756728..0e2f24f 100644
--- a/gyp/core.gypi
+++ b/gyp/core.gypi
@@ -48,8 +48,6 @@
         '<(skia_src_path)/core/SkBuffer.cpp',
         '<(skia_src_path)/core/SkCachedData.cpp',
         '<(skia_src_path)/core/SkCanvas.cpp',
-        '<(skia_src_path)/core/SkCanvasDrawable.cpp',
-        '<(skia_src_path)/core/SkCanvasDrawable.h',
         '<(skia_src_path)/core/SkChunkAlloc.cpp',
         '<(skia_src_path)/core/SkClipStack.cpp',
         '<(skia_src_path)/core/SkColor.cpp',
@@ -78,6 +76,7 @@
         '<(skia_src_path)/core/SkDistanceFieldGen.h',
         '<(skia_src_path)/core/SkDither.cpp',
         '<(skia_src_path)/core/SkDraw.cpp',
+        '<(skia_src_path)/core/SkDrawable.cpp',
         '<(skia_src_path)/core/SkDrawLooper.cpp',
         '<(skia_src_path)/core/SkDrawProcs.h',
         '<(skia_src_path)/core/SkEdgeBuilder.cpp',
@@ -255,6 +254,7 @@
         '<(skia_include_path)/core/SkDevice.h',
         '<(skia_include_path)/core/SkDither.h',
         '<(skia_include_path)/core/SkDraw.h',
+        '<(skia_include_path)/core/SkDrawable.h',
         '<(skia_include_path)/core/SkDrawFilter.h',
         '<(skia_include_path)/core/SkDrawLooper.h',
         '<(skia_include_path)/core/SkEndian.h',