Rename StageKey and related stuff.

R=robertphillips@google.com
Review URL: https://codereview.appspot.com/6785049

git-svn-id: http://skia.googlecode.com/svn/trunk@6130 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/effects/gradients/SkRadialGradient.cpp b/src/effects/gradients/SkRadialGradient.cpp
index dac1dc0..ee1ce66 100644
--- a/src/effects/gradients/SkRadialGradient.cpp
+++ b/src/effects/gradients/SkRadialGradient.cpp
@@ -487,7 +487,7 @@
                         const char* inputColor,
                         const TextureSamplerArray&) SK_OVERRIDE;
 
-    static StageKey GenKey(const GrEffect& s, const GrGLCaps& caps) { return 0; }
+    static EffectKey GenKey(const GrEffect& s, const GrGLCaps& caps) { return 0; }
 
 private: