Implement Porter Duff XP with a blend table

src/gpu/GrCaps.cpp

 
 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrCaps.h"
 #include "GrContextOptions.h"
@@ skipping 55 matching lines @@
                     fFloatPrecisions[s][p].fLogRangeLow,
                     fFloatPrecisions[s][p].fLogRangeHigh,
                     fFloatPrecisions[s][p].fBits);
             }
         }
     }
 
     return r;
 }
 
-void GrShaderCaps::applyOptionsOverrides(const GrContextOptions&) {
-    // Currently no overrides apply to shader caps.
+void GrShaderCaps::applyOptionsOverrides(const GrContextOptions& options) {
+    fDualSourceBlendingSupport = fDualSourceBlendingSupport && !options.fSuppressDualSourceBlending;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 GrCaps::GrCaps(const GrContextOptions& options) {
     fMipMapSupport = false;
     fNPOTTextureTileSupport = false;
     fTwoSidedStencilSupport = false;
     fStencilWrapOpsSupport = false;
     fDiscardRenderTargetSupport = false;
@@ skipping 124 matching lines @@
     SkASSERT(!fConfigTextureSupport[kUnknown_GrPixelConfig]);
 
     for (size_t i = 1; i < SK_ARRAY_COUNT(kConfigNames); ++i)  {
         r.appendf("%s is uploadable to a texture: %s\n",
                   kConfigNames[i],
                   gNY[fConfigTextureSupport[i]]);
     }
 
     return r;
 }