Add GrPaint stage for xfermodes.

src/gpu/GrDrawState.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 GrDrawState_DEFINED
 #define GrDrawState_DEFINED
 
 #include "GrBackendEffectFactory.h"
 #include "GrColor.h"
 #include "GrEffectStage.h"
+#include "GrPaint.h"
 #include "GrRefCnt.h"
 #include "GrRenderTarget.h"
 #include "GrStencil.h"
 #include "GrTemplates.h"
 #include "GrTexture.h"
 #include "GrTypesPriv.h"
 #include "effects/GrSimpleTextureEffect.h"
 
 #include "SkMatrix.h"
 #include "SkXfermode.h"
@@ skipping 22 matching lines @@
      * coverage rather than as input to the src/dst color blend step.
      *
      * The input color to the first enabled color-stage is either the constant color or interpolated
      * per-vertex colors, depending upon GrAttribBindings. The input to the first coverage stage is
      * either a constant coverage (usually full-coverage) or interpolated per-vertex coverage.
      *
      * See the documentation of kCoverageDrawing_StateBit for information about disabling the
      * the color / coverage distinction.
      *
      * Stages 0 through GrPaint::kTotalStages-1 are reserved for stages copied from the client's
-     * GrPaint. Stages GrPaint::kTotalStages through kNumStages-2 are earmarked for use by
-     * GrTextContext and GrPathRenderer-derived classes. kNumStages-1 is earmarked for clipping
-     * by GrClipMaskManager.
+     * GrPaint. Stage GrPaint::kTotalStages is earmarked for use by GrTextContext, GrPathRenderer-
+     * derived classes, and the rect/oval helper classes. GrPaint::kTotalStages+1 is earmarked for
+     * clipping by GrClipMaskManager. TODO: replace fixed size array of stages with variable size
+     * arrays of color and coverage stages.
      */
     enum {
-        kNumStages = 5,
+        kNumStages = GrPaint::kTotalStages + 2,
     };
 
     GrDrawState() {
 #if GR_DEBUG
         VertexAttributesUnitTest();
 #endif
         this->reset();
     }
 
     GrDrawState(const GrDrawState& state) {
@@ skipping 1153 matching lines @@
     int                                    fAttribIndices[kAttribIndexCount];
     GrVertexAttribArray<kVertexAttribCnt>  fVertexAttribs;
     GrEffectStage                          fStages[kNumStages];
 
     typedef GrRefCnt INHERITED;
 };
 
 GR_MAKE_BITFIELD_OPS(GrDrawState::BlendOptFlags);
 
 #endif