Switch GrEffect::onIsEqual signature back to GrEffect from GrEffectRef.

R=robertphillips@google.com
Review URL: https://codereview.appspot.com/7188046

git-svn-id: http://skia.googlecode.com/svn/trunk@7326 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/effects/GrConvolutionEffect.cpp b/src/gpu/effects/GrConvolutionEffect.cpp
index ffa5427..8968857 100644
--- a/src/gpu/effects/GrConvolutionEffect.cpp
+++ b/src/gpu/effects/GrConvolutionEffect.cpp
@@ -166,7 +166,7 @@
     return GrTBackendEffectFactory<GrConvolutionEffect>::getInstance();
 }
 
-bool GrConvolutionEffect::onIsEqual(const GrEffectRef& sBase) const {
+bool GrConvolutionEffect::onIsEqual(const GrEffect& sBase) const {
     const GrConvolutionEffect& s = CastEffect<GrConvolutionEffect>(sBase);
     return (this->texture(0) == s.texture(0) &&
             this->radius() == s.radius() &&