correctly copy constant coverage from GrPaint to GrDrawState

src/gpu/GrDrawState.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrDrawState.h"
 #include "GrPaint.h"
 
@@ skipping 28 matching lines @@
     for (int i = 0; i < paint.numCoverageStages(); ++i) {
         fCoverageStages.push_back(paint.getCoverageStage(i));
     }
 
     this->setRenderTarget(rt);
 
     fCommon.fViewMatrix = vm;
 
     // These have no equivalent in GrPaint, set them to defaults
     fCommon.fBlendConstant = 0x0;
-    fCommon.fCoverage = 0xffffffff;
     fCommon.fDrawFace = kBoth_DrawFace;
     fCommon.fStencilSettings.setDisabled();
     this->resetStateFlags();
 
     // Enable the clip bit
     this->enableState(GrDrawState::kClip_StateBit);
 
     this->setColor(paint.getColor());
+    this->setCoverage4(paint.getCoverage());
     this->setState(GrDrawState::kDither_StateBit, paint.isDither());
     this->setState(GrDrawState::kHWAntialias_StateBit, paint.isAntiAlias());
 
     this->setBlendFunc(paint.getSrcBlendCoeff(), paint.getDstBlendCoeff());
     this->setColorFilter(paint.getColorFilterColor(), paint.getColorFilterMode());
     this->setCoverage(paint.getCoverage());
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ skipping 407 matching lines @@
         fDrawState->fColorStages[s].saveCoordChange(&fSavedCoordChanges[i]);
         fDrawState->fColorStages[s].localCoordChange(coordChangeMatrix);
     }
 
     int numCoverageStages = fDrawState->numCoverageStages();
     for (int s = 0; s < numCoverageStages; ++s, ++i) {
         fDrawState->fCoverageStages[s].saveCoordChange(&fSavedCoordChanges[i]);
         fDrawState->fCoverageStages[s].localCoordChange(coordChangeMatrix);
     }
 }