Rename GrSamplerState to GrEffectStage.

R=robertphillips@google.com
Review URL: https://codereview.appspot.com/6777053

git-svn-id: http://skia.googlecode.com/svn/trunk@6135 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrSWMaskHelper.cpp b/src/gpu/GrSWMaskHelper.cpp
index ec0dbf1..68d24c3 100644
--- a/src/gpu/GrSWMaskHelper.cpp
+++ b/src/gpu/GrSWMaskHelper.cpp
@@ -212,7 +212,7 @@
         kPathMaskStage = GrPaint::kTotalStages,
     };
     GrAssert(!drawState->isStageEnabled(kPathMaskStage));
-    drawState->sampler(kPathMaskStage)->reset();
+    drawState->stage(kPathMaskStage)->reset();
     drawState->createTextureEffect(kPathMaskStage, texture);
     GrScalar w = GrIntToScalar(rect.width());
     GrScalar h = GrIntToScalar(rect.height());