Make GrClipMaskManager stateless and push GrPipelineBuilder construction downstack

src/gpu/GrPipelineBuilder.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrPipelineBuilder_DEFINED
 #define GrPipelineBuilder_DEFINED
 
@@ skipping 180 matching lines @@
      * @param target  The render target to set.
      */
     void setRenderTarget(GrRenderTarget* target) { fRenderTarget.reset(SkSafeRef(target)); }
 
     /// @}
 
     ///////////////////////////////////////////////////////////////////////////
     /// @name Stencil
     ////
 
-    bool hasUserStencilSettings() const {
-        return &GrUserStencilSettings::kUnused != fUserStencilSettings;
-    }
+    bool hasUserStencilSettings() const { return !fUserStencilSettings->isUnused(); }
     const GrUserStencilSettings* getUserStencil() const { return fUserStencilSettings; }
 
     /**
      * Sets the user stencil settings for the next draw.
      * This class only stores pointers to stencil settings objects.
      * The caller guarantees the pointer will remain valid until it
      * changes or goes out of scope.
      * @param settings  the stencil settings to use.
      */
     void setUserStencil(const GrUserStencilSettings* settings) { fUserStencilSettings = settings; }
@@ skipping 120 matching lines @@
     DrawFace                                fDrawFace;
     mutable SkAutoTUnref<const GrXPFactory> fXPFactory;
     FragmentProcessorArray                  fColorFragmentProcessors;
     FragmentProcessorArray                  fCoverageFragmentProcessors;
 
     friend class GrPipeline;
     friend class GrDrawTarget;
 };
 
 #endif