Add Coverage Drawing XP

include/gpu/GrXferProcessor.h

Index: include/gpu/GrXferProcessor.h
diff --git a/include/gpu/GrXferProcessor.h b/include/gpu/GrXferProcessor.h
index bab6141f440de9ff7f5a90f4f328a8638f0dbbf0..80e375c03c36279fb1c9f68f07a8b0dc9b6d5492 100644
--- a/include/gpu/GrXferProcessor.h
+++ b/include/gpu/GrXferProcessor.h
@@ -86,11 +86,9 @@ public:
      * A caller who calls this function on a XP is required to honor the returned OptFlags
      * and color values for its draw.
      */
-    // TODO: remove need for isCoverageDrawing once coverageDrawing is its own XP.
     // TODO: remove need for colorWriteDisabled once colorWriteDisabled is its own XP.
     virtual OptFlags getOptimizations(const GrProcOptInfo& colorPOI,
                                       const GrProcOptInfo& coveragePOI,
-                                      bool isCoverageDrawing,
                                       bool colorWriteDisabled,
                                       bool doesStencilWrite,
                                       GrColor* overrideColor,
@@ -127,7 +125,6 @@ public:
         return this->onIsEqual(that);
     }
    
-
 protected:
     GrXferProcessor() : fWillReadDstColor(false) {}
 
@@ -138,11 +135,6 @@ protected:
      */
     void setWillReadDstColor() { fWillReadDstColor = true; }
 
-    /**
-     * Subclass implements this to support getConstantColorComponents(...).
-     */
-    virtual void onComputeInvariantOutput(GrInvariantOutput* inout) const = 0;
-
 private:
     virtual bool onIsEqual(const GrXferProcessor&) const = 0;
 
@@ -181,30 +173,27 @@ public:
      * fractional pixel coverage generated by the fragment shader.
      *
      * This function considers the known color and coverage input into the xfer processor and
-     * certain state information (isCoverageDrawing and colorWriteDisabled) to determine whether
+     * certain state information (colorWriteDisabled) to determine whether
      * coverage can be handled correctly.
      */
-    // TODO: remove need for isCoverageDrawing once coverageDrawing is its own XP.
     // TODO: remove need for colorWriteDisabled once colorWriteDisabled is its own XP.
     virtual bool canApplyCoverage(const GrProcOptInfo& colorPOI, const GrProcOptInfo& coveragePOI,
-                                  bool isCoverageDrawing, bool colorWriteDisabled) const = 0;
+                                  bool colorWriteDisabled) const = 0;
 
     /**
      * This function returns true if the destination pixel values will be read for blending during
      * draw.
      */
-    // TODO: remove need for isCoverageDrawing once coverageDrawing is its own XP.
     // TODO: remove need for colorWriteDisabled once only XP can read dst.
     virtual bool willBlendWithDst(const GrProcOptInfo& colorPOI, const GrProcOptInfo& coveragePOI,
-                                  bool isCoverageDrawing, bool colorWriteDisabled) const = 0;
+                                  bool colorWriteDisabled) const = 0;
 
     /**
      * Determines whether multiplying the computed per-pixel color by the pixel's fractional
      * coverage before the blend will give the correct final destination color. In general it
      * will not as coverage is applied after blending.
      */
-    // TODO: remove need for isCoverageDrawing once coverageDrawing is its own XP.
-    virtual bool canTweakAlphaForCoverage(bool isCoverageDrawing) const = 0;
+    virtual bool canTweakAlphaForCoverage() const = 0;
 
     virtual bool getOpaqueAndKnownColor(const GrProcOptInfo& colorPOI,
                                         const GrProcOptInfo& coveragePOI, GrColor* solidColor,