Remove gpu shader optimatization for solid white or trans black colors

src/gpu/gl/GrGLProgramDesc.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrGLProgramDesc_DEFINED
 #define GrGLProgramDesc_DEFINED
 
@@ skipping 84 matching lines @@
     }
 
     static bool Less(const GrGLProgramDesc& a, const GrGLProgramDesc& b) {
         return memcmp(a.asKey(), b.asKey(), a.keyLength() & ~0x3) < 0;
     }
 
 private:
     // Specifies where the initial color comes from before the stages are applied.
     enum ColorInput {
         kSolidWhite_ColorInput,
-        kTransBlack_ColorInput,
         kAttribute_ColorInput,
         kUniform_ColorInput,
 
         kColorInputCnt
     };
 
     enum CoverageOutput {
         // modulate color and coverage, write result as the color output.
         kModulate_CoverageOutput,
         // Writes color*coverage as the primary color output and also writes coverage as the
@@ skipping 136 matching lines @@
     // GrGLProgram and GrGLShaderBuilder read the private fields to generate code. TODO: Split out
     // part of GrGLShaderBuilder that is used by effects so that this header doesn't need to be
     // visible to GrGLEffects. Then make public accessors as necessary and remove friends.
     friend class GrGLProgram;
     friend class GrGLShaderBuilder;
     friend class GrGLFullShaderBuilder;
     friend class GrGLFragmentOnlyShaderBuilder;
 };
 
 #endif