Expand modulate, add, subtract, extract component glsl helpers.

src/gpu/gl/GrGLProgram.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef GrGLProgram_DEFINED
 #define GrGLProgram_DEFINED
@@ skipping 107 matching lines @@
                 const GrGLProgramDesc& desc,
                 const GrEffectStage* stages[]);
 
     bool succeeded() const { return 0 != fProgramID; }
 
     /**
      *  This is the heavy initialization routine for building a GLProgram.
      */
     bool genProgram(const GrEffectStage* stages[]);
 
-    void genInputColor(GrGLShaderBuilder* builder, SkString* inColor);
+    GrSLConstantVec genInputColor(GrGLShaderBuilder* builder, SkString* inColor);
+
+    GrSLConstantVec genInputCoverage(GrGLShaderBuilder* builder, SkString* inCoverage);
 
     void genGeometryShader(GrGLShaderBuilder* segments) const;
 
     typedef GrGLUniformManager::UniformHandle UniformHandle;
 
-    void genUniformCoverage(GrGLShaderBuilder* segments, SkString* inOutCoverage);
-
     // Creates a GL program ID, binds shader attributes to GL vertex attrs, and links the program
     bool bindOutputsAttribsAndLinkProgram(const GrGLShaderBuilder& builder,
                                           bool bindColorOut,
                                           bool bindDualSrcOut);
 
     // Sets the texture units for samplers
     void initSamplerUniforms();
 
     bool compileShaders(const GrGLShaderBuilder& builder);
 
@@ skipping 59 matching lines @@
     GrGLProgramDesc             fDesc;
     const GrGLContext&          fContext;
 
     GrGLUniformManager          fUniformManager;
     UniformHandles              fUniformHandles;
 
     typedef GrRefCnt INHERITED;
 };
 
 #endif