Force input coverage to be only a byte in gpu shaders.
Prime coverage invariant output calculations with single component
BUG=skia:
Review URL: https://codereview.chromium.org/649783003
diff --git a/src/gpu/GrAARectRenderer.cpp b/src/gpu/GrAARectRenderer.cpp
index ae8a06c..6843aca 100644
--- a/src/gpu/GrAARectRenderer.cpp
+++ b/src/gpu/GrAARectRenderer.cpp
@@ -265,7 +265,7 @@
extern const GrVertexAttrib gAARectAttribs[] = {
{kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding},
{kVec4ub_GrVertexAttribType, sizeof(SkPoint), kColor_GrVertexAttribBinding},
- {kVec4ub_GrVertexAttribType, sizeof(SkPoint) + sizeof(SkColor), kCoverage_GrVertexAttribBinding},
+ {kUByte_GrVertexAttribType, sizeof(SkPoint) + sizeof(SkColor), kCoverage_GrVertexAttribBinding},
};
// Should the coverage be multiplied into the color attrib or use a separate attrib.