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/effects/gradients/SkGradientShaderPriv.h b/src/effects/gradients/SkGradientShaderPriv.h
index a34e4ab..954acb2 100644
--- a/src/effects/gradients/SkGradientShaderPriv.h
+++ b/src/effects/gradients/SkGradientShaderPriv.h
@@ -255,7 +255,7 @@
                                     SkScalar** stops,
                                     SkShader::TileMode* tm);
 
-    virtual bool onIsEqual(const GrEffectRef& effect) const SK_OVERRIDE;
+    virtual bool onIsEqual(const GrEffect& effect) const SK_OVERRIDE;
 
 private: