Potentially optimize some GrGLEffects for known input color values

src/gpu/effects/GrTextureDomainEffect.cpp

Index: src/gpu/effects/GrTextureDomainEffect.cpp
diff --git a/src/gpu/effects/GrTextureDomainEffect.cpp b/src/gpu/effects/GrTextureDomainEffect.cpp
index eca99d73a86b7f64d02028e9505592c2f905e17d..dafbb076bc20b9e52c7137cb3014cc1914e03124 100644
--- a/src/gpu/effects/GrTextureDomainEffect.cpp
+++ b/src/gpu/effects/GrTextureDomainEffect.cpp
@@ -19,7 +19,7 @@ public:
                           const GrDrawEffect&,
                           EffectKey,
                           const char* outputColor,
-                          const char* inputColor,
+                          const GrGLSLExpr4& inputColor,
                           const TransformedCoordsArray&,
                           const TextureSamplerArray&) SK_OVERRIDE;
 
@@ -44,7 +44,7 @@ void GrGLTextureDomainEffect::emitCode(GrGLShaderBuilder* builder,
                                        const GrDrawEffect& drawEffect,
                                        EffectKey key,
                                        const char* outputColor,
-                                       const char* inputColor,
+                                       const GrGLSLExpr4& inputColor,
                                        const TransformedCoordsArray& coords,
                                        const TextureSamplerArray& samplers) {
     const GrTextureDomainEffect& texDom = drawEffect.castEffect<GrTextureDomainEffect>();