Create xfer processor backend.

src/gpu/gl/GrGLProgram.h

Index: src/gpu/gl/GrGLProgram.h
diff --git a/src/gpu/gl/GrGLProgram.h b/src/gpu/gl/GrGLProgram.h
index 36bf8602330e55c9a1fe9f5e12c8aec0fafd29f9..ea8be85251c6bcfaf3e98218a80cb981fee41117 100644
--- a/src/gpu/gl/GrGLProgram.h
+++ b/src/gpu/gl/GrGLProgram.h
@@ -141,6 +141,7 @@ protected:
                 GrGLuint programID,
                 const UniformInfoArray&,
                 GrGLInstalledGeoProc* geometryProcessor,
+                GrGLInstalledXferProc* xferProcessor,
                 GrGLInstalledFragProcs* fragmentProcessors);
 
     // Sets the texture units for samplers.
@@ -180,6 +181,7 @@ protected:
 
     // the installed effects
     SkAutoTDelete<GrGLInstalledGeoProc> fGeometryProcessor;
+    SkAutoTDelete<GrGLInstalledXferProc> fXferProcessor;
     SkAutoTUnref<GrGLInstalledFragProcs> fFragmentProcessors;
 
     GrProgramDesc fDesc;
@@ -205,6 +207,7 @@ protected:
                         const BuiltinUniformHandles&,
                         GrGLuint programID,
                         const UniformInfoArray&,
+                        GrGLInstalledXferProc* xferProcessor,
                         GrGLInstalledFragProcs* fragmentProcessors);
     virtual void onSetMatrixAndRenderTargetHeight(const GrOptDrawState&);
 
@@ -223,6 +226,7 @@ private:
                     const BuiltinUniformHandles&,
                     GrGLuint programID,
                     const UniformInfoArray&,
+                    GrGLInstalledXferProc* xferProcessor,
                     GrGLInstalledFragProcs* fragmentProcessors,
                     const SeparableVaryingInfoArray& separableVaryings);
     virtual void didSetData(GrGpu::DrawType) SK_OVERRIDE;
@@ -252,7 +256,8 @@ private:
                           const BuiltinUniformHandles&,
                           GrGLuint programID,
                           const UniformInfoArray&,
-                          GrGLInstalledFragProcs* fragmentProcessors,
+                          GrGLInstalledXferProc* xp,
+                          GrGLInstalledFragProcs* fps,
                           int texCoordSetCnt);
     virtual void didSetData(GrGpu::DrawType) SK_OVERRIDE;
     virtual void setTransformData(const GrPendingFragmentStage&,