Allow GrGLEffects to produce variable length keys.

src/gpu/effects/GrDitherEffect.cpp

Index: src/gpu/effects/GrDitherEffect.cpp
diff --git a/src/gpu/effects/GrDitherEffect.cpp b/src/gpu/effects/GrDitherEffect.cpp
index 37354c6d7d6d3bedfa9bfadfeee42f4e38508cc3..a431897a4eaa2a987bb902f6a0504020bb3ed09b 100644
--- a/src/gpu/effects/GrDitherEffect.cpp
+++ b/src/gpu/effects/GrDitherEffect.cpp
@@ -72,7 +72,7 @@ public:
 
     virtual void emitCode(GrGLShaderBuilder* builder,
                           const GrDrawEffect& drawEffect,
-                          EffectKey key,
+                          const GrEffectKey& key,
                           const char* outputColor,
                           const char* inputColor,
                           const TransformedCoordsArray&,
@@ -89,7 +89,7 @@ GLDitherEffect::GLDitherEffect(const GrBackendEffectFactory& factory,
 
 void GLDitherEffect::emitCode(GrGLShaderBuilder* builder,
                               const GrDrawEffect& drawEffect,
-                              EffectKey key,
+                              const GrEffectKey& key,
                               const char* outputColor,
                               const char* inputColor,
                               const TransformedCoordsArray&,