Revert of Begin weaning GrClipMaskManager off of GrDrawTarget (take 2)

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 137 matching lines @@
     /**
      * Installs a GrXPFactory. This object controls how src color, fractional pixel coverage,
      * and the dst color are blended.
      */
     const GrXPFactory* setXPFactory(const GrXPFactory* xpFactory) {
         fXPFactory.reset(SkSafeRef(xpFactory));
         return xpFactory;
     }
 
     /**
+     * Sets a GrXPFactory that will ignore src color and perform a set operation between the draws
+     * output coverage and the destination. This is useful to render coverage masks as CSG.
+     */
+    void setCoverageSetOpXPFactory(SkRegion::Op regionOp, bool invertCoverage = false) {
+        fXPFactory.reset(GrCoverageSetOpXPFactory::Create(regionOp, invertCoverage));
+    }
+
+    /**
      * Sets a GrXPFactory that disables color writes to the destination. This is useful when
      * rendering to the stencil buffer.
      */
     void setDisableColorXPFactory() {
         fXPFactory.reset(GrDisableColorXPFactory::Create());
     }
 
     const GrXPFactory* getXPFactory() const {
         return fXPFactory;
     }
@@ skipping 203 matching lines @@
     mutable SkAutoTUnref<const GrXPFactory> fXPFactory;
     FragmentProcessorArray                  fColorFragmentProcessors;
     FragmentProcessorArray                  fCoverageFragmentProcessors;
     GrClip                                  fClip;
 
     friend class GrPipeline;
     friend class GrDrawTarget;
 };
 
 #endif