Fix assert


git-svn-id: http://skia.googlecode.com/svn/trunk@2831 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrDrawState.h b/src/gpu/GrDrawState.h
index 8be4f3f..24a48c1 100644
--- a/src/gpu/GrDrawState.h
+++ b/src/gpu/GrDrawState.h
@@ -184,7 +184,7 @@
      * are color-computing).
      */
     void setFirstCoverageStage(int firstCoverageStage) {
-        GrAssert((unsigned)firstCoverageStage < kNumStages);
+        GrAssert((unsigned)firstCoverageStage <= kNumStages);
         fFirstCoverageStage = firstCoverageStage; 
     }