Fixed Windows compiler complaints

http://codereview.appspot.com/6392044



git-svn-id: http://skia.googlecode.com/svn/trunk@4511 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrDrawTarget.cpp b/src/gpu/GrDrawTarget.cpp
index c2a308e..60095ab 100644
--- a/src/gpu/GrDrawTarget.cpp
+++ b/src/gpu/GrDrawTarget.cpp
@@ -540,7 +540,7 @@
 }
 
 bool GrDrawTarget::StageUsesTexCoords(GrVertexLayout layout, int stage) {
-    return layout & gStageTexCoordMasks[stage];
+    return SkToBool(layout & gStageTexCoordMasks[stage]);
 }
 
 bool GrDrawTarget::reserveVertexAndIndexSpace(GrVertexLayout vertexLayout,