Don't use NULL GrOptDrawState to indicate that draw should be skipped.

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 12 matching lines @@
 /**
  * Class that holds an optimized version of a GrDrawState. It is meant to be an immutable class,
  * and contains all data needed to set the state for a gpu draw.
  */
 class GrOptDrawState : public SkRefCnt {
 public:
     SK_DECLARE_INST_COUNT(GrOptDrawState)
 
     typedef GrClipMaskManager::ScissorState ScissorState;
 
-    /**
-     * Returns a snapshot of the current optimized state. The GrOptDrawState is reffed and ownership
-     * is given to the caller.
-     */
-    static GrOptDrawState* Create(const GrDrawState& drawState,
-                                  GrGpu*,
-                                  const ScissorState&,
-                                  const GrDeviceCoordTexture* dstCopy,
-                                  GrGpu::DrawType drawType);
+    GrOptDrawState(const GrDrawState& drawState, GrGpu*, const ScissorState&,
+                   const GrDeviceCoordTexture* dstCopy, GrGpu::DrawType);
 
     bool operator== (const GrOptDrawState& that) const;
     bool operator!= (const GrOptDrawState& that) const { return !(*this == that); }
 
     ///////////////////////////////////////////////////////////////////////////
     /// @name Vertex Attributes
     ////
 
     enum {
         kMaxVertexAttribCnt = kLast_GrVertexAttribBinding + 4,
@@ skipping 123 matching lines @@
     /// @}
 
 
     ///////////////////////////////////////////////////////////////////////////
     /// @name Boolean Queries
     ////
 
     bool isDitherState() const { return SkToBool(fFlags & kDither_Flag); }
     bool isHWAntialiasState() const { return SkToBool(fFlags & kHWAA_Flag); }
     bool isColorWriteDisabled() const { return SkToBool(fFlags & kDisableColorWrite_Flag); }
+    bool mustSkip() const { return NULL == this->getRenderTarget(); }
 
     /// @}
 
     /**
      * Gets whether the target is drawing clockwise, counterclockwise,
      * or both faces.
      * @return the current draw face(s).
      */
     GrDrawState::DrawFace getDrawFace() const { return fDrawFace; }
 
     /// @}
 
     ///////////////////////////////////////////////////////////////////////////
 
 
     const GrProgramDesc& programDesc() const { return fDesc; }
 
 private:
     /**
-     * Constructs and optimized drawState out of a GrRODrawState.
-     */
-    GrOptDrawState(const GrDrawState& drawState, GrDrawState::BlendOpt,
-                   GrBlendCoeff optSrcCoeff, GrBlendCoeff optDstCoeff,
-                   GrGpu*, const ScissorState&, const GrDeviceCoordTexture* dstCopy,
-                   GrGpu::DrawType);
-
-    /**
      * Loops through all the color stage effects to check if the stage will ignore color input or
      * always output a constant color. In the ignore color input case we can ignore all previous
      * stages. In the constant color case, we can ignore all previous stages and
      * the current one and set the state color to the constant color.
      */
     void computeEffectiveColorStages(const GrDrawState& ds, GrProgramDesc::DescInfo*,
                                      int* firstColorStageIdx, uint8_t* fixFunctionVAToRemove);
 
     /**
      * Loops through all the coverage stage effects to check if the stage will ignore color input.
@@ skipping 63 matching lines @@
     int                                 fNumColorStages;
 
     SkAutoSTArray<4, GrVertexAttrib> fOptVA;
 
     GrProgramDesc fDesc;
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif