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/gpu/gl/GrGLEffect.cpp b/src/gpu/gl/GrGLEffect.cpp
index 3f8417c..b53a1cf 100644
--- a/src/gpu/gl/GrGLEffect.cpp
+++ b/src/gpu/gl/GrGLEffect.cpp
@@ -20,12 +20,12 @@
 void GrGLEffect::setData(const GrGLUniformManager&, const GrEffect&) {
 }
 
-GrGLEffect::StageKey GrGLEffect::GenTextureKey(const GrEffect& effect,
+GrGLEffect::EffectKey GrGLEffect::GenTextureKey(const GrEffect& effect,
                                                            const GrGLCaps& caps) {
-    StageKey key = 0;
+    EffectKey key = 0;
     for (int index = 0; index < effect.numTextures(); ++index) {
         const GrTextureAccess& access = effect.textureAccess(index);
-        StageKey value = GrGLShaderBuilder::KeyForTextureAccess(access, caps) << index;
+        EffectKey value = GrGLShaderBuilder::KeyForTextureAccess(access, caps) << index;
         GrAssert(0 == (value & key)); // keys for each access ought not to overlap
         key |= value;
     }