Allow GrGLEffects to produce variable length keys.

src/gpu/gl/GrGLVertexEffect.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 GrGLVertexEffect_DEFINED
 #define GrGLVertexEffect_DEFINED
 
 #include "GrGLEffect.h"
 
 /**
  * If a GL effect needs a GrGLFullShaderBuilder* object to emit vertex code, then it must inherit
  * from this class. Since paths don't have vertices, this class is only meant to be used internally
  * by skia, for special cases.
  */
 class GrGLVertexEffect : public GrGLEffect {
 public:
     GrGLVertexEffect(const GrBackendEffectFactory& factory)
         : INHERITED(factory) { fIsVertexEffect = true; }
 
     /**
      * This is similar to emitCode() in the base class, except it takes a full shader builder.
      * This allows the effect subclass to emit vertex code.
      */
     virtual void emitCode(GrGLFullShaderBuilder* builder,
                           const GrDrawEffect& drawEffect,
-                          EffectKey key,
+                          const GrEffectKey& key,
                           const char* outputColor,
                           const char* inputColor,
                           const TransformedCoordsArray& coords,
                           const TextureSamplerArray& samplers) = 0;
 
     /**
      * Provide a default override for base class's emitCode() function.
      */
     virtual void emitCode(GrGLShaderBuilder* builder,
                           const GrDrawEffect& drawEffect,
-                          EffectKey key,
+                          const GrEffectKey& key,
                           const char* outputColor,
                           const char* inputColor,
                           const TransformedCoordsArray& coords,
                           const TextureSamplerArray& samplers) SK_OVERRIDE {
         SkFAIL("GrGLVertexEffect requires GrGLFullShaderBuilder* overload for emitCode().");
     }
 
 private:
     typedef GrGLEffect INHERITED;
 };
 
 #endif