Add GrEllipseEdgeEffect.

Adds the effect that replaces the old oval rendering code. Also hooks in code to set attribute names and indices for effects.

Author: jvanverth@google.com

Review URL: https://chromiumcodereview.appspot.com/12462008

git-svn-id: http://skia.googlecode.com/svn/trunk@8092 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrSWMaskHelper.cpp b/src/gpu/GrSWMaskHelper.cpp
index 9682ec4..fe9fd82 100644
--- a/src/gpu/GrSWMaskHelper.cpp
+++ b/src/gpu/GrSWMaskHelper.cpp
@@ -193,7 +193,8 @@
     }
     enum {
         // the SW path renderer shares this stage with glyph
-        // rendering (kGlyphMaskStage in GrBatchedTextContext)
+        // rendering (kGlyphMaskStage in GrTextContext)
+        // && edge rendering (kEdgeEffectStage in GrContext)
         kPathMaskStage = GrPaint::kTotalStages,
     };
     GrAssert(!drawState->isStageEnabled(kPathMaskStage));