Potentially optimize some GrGLEffects for known input color values

src/gpu/effects/GrCustomCoordsTextureEffect.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 "GrCustomCoordsTextureEffect.h"
 #include "gl/GrGLEffect.h"
 #include "gl/GrGLSL.h"
 #include "gl/GrGLTexture.h"
 #include "gl/GrGLVertexEffect.h"
 #include "GrTBackendEffectFactory.h"
 #include "GrTexture.h"
 
 class GrGLCustomCoordsTextureEffect : public GrGLVertexEffect {
 public:
     GrGLCustomCoordsTextureEffect(const GrBackendEffectFactory& factory, const GrDrawEffect& drawEffect)
         : INHERITED (factory) {}
 
     virtual void emitCode(GrGLFullShaderBuilder* builder,
                           const GrDrawEffect& drawEffect,
                           EffectKey key,
                           const char* outputColor,
-                          const char* inputColor,
+                          const GrGLSLExpr4& inputColor,
                           const TransformedCoordsArray&,
                           const TextureSamplerArray& samplers) SK_OVERRIDE {
         SkASSERT(1 == drawEffect.castEffect<GrCustomCoordsTextureEffect>().numVertexAttribs());
 
         SkString fsCoordName;
         const char* vsVaryingName;
         const char* fsVaryingNamePtr;
         builder->addVarying(kVec2f_GrSLType, "textureCoords", &vsVaryingName, &fsVaryingNamePtr);
         fsCoordName = fsVaryingNamePtr;
 
@@ skipping 61 matching lines @@
     };
     SkShader::TileMode tileModes[] = {
         kTileModes[random->nextULessThan(SK_ARRAY_COUNT(kTileModes))],
         kTileModes[random->nextULessThan(SK_ARRAY_COUNT(kTileModes))],
     };
     GrTextureParams params(tileModes, random->nextBool() ? GrTextureParams::kBilerp_FilterMode :
                                                            GrTextureParams::kNone_FilterMode);
 
     return GrCustomCoordsTextureEffect::Create(textures[texIdx], params);
 }