Update XPF invariant info to not account for conflation

include/gpu/GrPaint.h

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef GrPaint_DEFINED
@@ skipping 111 matching lines @@
 
         fColorStages = paint.fColorStages;
         fCoverageStages = paint.fCoverageStages;
 
         fXPFactory.reset(SkRef(paint.getXPFactory()));
 
         return *this;
     }
 
     /**
-     * Returns true if isOpaque would return true and the paint represents a solid constant color
-     * draw. If the result is true, constantColor will be updated to contain the constant color.
+     * Returns true if the paint's output color will be constant after blending. If the result is
+     * true, constantColor will be updated to contain the constant color. Note that we can conflate
+     * coverage and color, so the actual values written to pixels with partial coverage may still
+     * not seem constant, even if this function returns true.
      */
-    bool isOpaqueAndConstantColor(GrColor* constantColor) const;
+    bool isConstantBlendedColor(GrColor* constantColor) const;
 
 private:
     mutable SkAutoTUnref<const GrXPFactory> fXPFactory;
     SkSTArray<4, GrFragmentStage>   fColorStages;
     SkSTArray<2, GrFragmentStage>   fCoverageStages;
 
     bool                            fAntiAlias;
     bool                            fDither;
 
     GrColor                         fColor;
 };
 
 #endif