Make skpaint->grpaint flow work for composing draws

tests/GpuColorFilterTest.cpp

 
 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkColorFilter.h"
 #include "Test.h"
@@ skipping 44 matching lines @@
         kB = kB_GrColorComponentFlag,
         kA = kA_GrColorComponentFlag,
         kRGB = kRGB_GrColorComponentFlags,
         kRGBA = kRGBA_GrColorComponentFlags
     };
 
     // Note: below, SkColors are non-premultiplied, where as GrColors are premultiplied.
 
     const SkColor c1 = SkColorSetARGB(200, 200, 200, 200);
     const SkColor c2 = SkColorSetARGB(60, 60, 60, 60);
-    const GrColor gr_c1 = SkColor2GrColor(c1);
-    const GrColor gr_c2 = SkColor2GrColor(c2);
+    const GrColor gr_c1 = SkColorToPremulGrColor(c1);
+    const GrColor gr_c2 = SkColorToPremulGrColor(c2);
 
     const GrColor gr_black = GrColorPackA4(0);
     const GrColor gr_white = GrColorPackA4(255);
     const GrColor gr_whiteTrans = GrColorPackA4(128);
 
     GetConstantComponentTestCase filterTests[] = {
         // A color filtered with Clear produces black.
         { kRGBA, gr_white, SK_ColorBLACK, SkXfermode::kClear_Mode, kRGBA, gr_black },
         { kRGBA, gr_c1,    SK_ColorWHITE, SkXfermode::kClear_Mode, kRGBA, gr_black },
         { kR,    gr_white, c1,            SkXfermode::kClear_Mode, kRGBA, gr_black },
@@ skipping 46 matching lines @@
         GrContext* grContext = factory->get(glType);
         if (nullptr == grContext) {
             continue;
         }
 
         test_getConstantColorComponents(reporter, grContext);
     }
 }
 
 #endif