Create helper functions to use in computeInvariantOutput calls

src/effects/gradients/SkGradientShader.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGradientShaderPriv.h"
 #include "SkLinearGradient.h"
 #include "SkRadialGradient.h"
@@ skipping 1195 matching lines @@
             fTextureAccess.getParams().getTileModeX() ==
                 s.fTextureAccess.getParams().getTileModeX() &&
             this->useAtlas() == s.useAtlas() &&
             fCoordTransform.getMatrix().cheapEqualTo(s.fCoordTransform.getMatrix());
     }
 
     return false;
 }
 
 void GrGradientEffect::onComputeInvariantOutput(InvariantOutput* inout) const {
-    if (fIsOpaque && inout->isOpaque()) {
-        inout->fValidFlags = kA_GrColorComponentFlag;
+    if (fIsOpaque) {
+        inout->mulByUnknownOpaqueColor();
     } else {
-        inout->fValidFlags = 0;
+        inout->mulByUnknownColor();
     }
-    inout->fIsSingleComponent = false;
 }
 
 int GrGradientEffect::RandomGradientParams(SkRandom* random,
                                            SkColor colors[],
                                            SkScalar** stops,
                                            SkShader::TileMode* tm) {
     int outColors = random->nextRangeU(1, kMaxRandomGradientColors);
 
     // if one color, omit stops, otherwise randomly decide whether or not to
     if (outColors == 1 || (outColors >= 2 && random->nextBool())) {
         *stops = NULL;
     }
 
     SkScalar stop = 0.f;
     for (int i = 0; i < outColors; ++i) {
         colors[i] = random->nextU();
         if (*stops) {
             (*stops)[i] = stop;
             stop = i < outColors - 1 ? stop + random->nextUScalar1() * (1.f - stop) : 1.f;
         }
     }
     *tm = static_cast<SkShader::TileMode>(random->nextULessThan(SkShader::kTileModeCount));
 
     return outColors;
 }
 
 #endif