Add XferProcessor factory in GrPaint and GrDrawState.

src/gpu/GrOptDrawState.h

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrOptDrawState_DEFINED
 #define GrOptDrawState_DEFINED
 
@@ skipping 66 matching lines @@
 
     int numColorStages() const { return fNumColorStages; }
     int numCoverageStages() const { return fFragmentStages.count() - fNumColorStages; }
     int numFragmentStages() const { return fFragmentStages.count(); }
     int numTotalStages() const {
          return this->numFragmentStages() + (this->hasGeometryProcessor() ? 1 : 0);
     }
 
     bool hasGeometryProcessor() const { return SkToBool(fGeometryProcessor.get()); }
     const GrGeometryProcessor* getGeometryProcessor() const { return fGeometryProcessor.get(); }
+
+    const GrXferProcessor* getXferProcessor() const { return fXferProcessor.get(); }
+
     const GrPendingFragmentStage& getColorStage(int idx) const {
         SkASSERT(idx < this->numColorStages());
         return fFragmentStages[idx];
     }
     const GrPendingFragmentStage& getCoverageStage(int idx) const {
         SkASSERT(idx < this->numCoverageStages());
         return fFragmentStages[fNumColorStages + idx];
     }
     const GrPendingFragmentStage& getFragmentStage(int idx) const {
         return fFragmentStages[idx];
@@ skipping 126 matching lines @@
 
     enum Flags {
         kDither_Flag            = 0x1,
         kHWAA_Flag              = 0x2,
         kDisableColorWrite_Flag = 0x4,
     };
 
     typedef GrPendingIOResource<GrRenderTarget, kWrite_GrIOType> RenderTarget;
     typedef SkSTArray<8, GrPendingFragmentStage> FragmentStageArray;
     typedef GrPendingProgramElement<const GrGeometryProcessor> ProgramGeometryProcessor;
+    typedef GrPendingProgramElement<const GrXferProcessor> ProgramXferProcessor;
     RenderTarget                        fRenderTarget;
     ScissorState                        fScissorState;
     GrColor                             fColor;
     SkMatrix                            fViewMatrix;
     GrColor                             fBlendConstant;
     GrStencilSettings                   fStencilSettings;
     uint8_t                             fCoverage;
     GrDrawState::DrawFace               fDrawFace;
     GrDeviceCoordTexture                fDstCopy;
     GrBlendCoeff                        fSrcBlend;
     GrBlendCoeff                        fDstBlend;
     uint32_t                            fFlags;
     ProgramGeometryProcessor            fGeometryProcessor;
+    ProgramXferProcessor                fXferProcessor;
     FragmentStageArray                  fFragmentStages;
 
     // This function is equivalent to the offset into fFragmentStages where coverage stages begin.
     int                                 fNumColorStages;
 
     GrProgramDesc fDesc;
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif