Don't use GrDrawTarget's AA state bit to convey whether to do custom-aa

Review URL: http://codereview.appspot.com/5314061/



git-svn-id: http://skia.googlecode.com/svn/trunk@2539 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrGpuGL.cpp b/src/gpu/GrGpuGL.cpp
index b27815b..077cdd9 100644
--- a/src/gpu/GrGpuGL.cpp
+++ b/src/gpu/GrGpuGL.cpp
@@ -1798,7 +1798,7 @@
                 fHWAAState.fMSAAEnabled = false;
             }
         } else if (fCurrDrawState.fRenderTarget->isMultisampled() &&
-                   !!(kAntialias_StateBit & fCurrDrawState.fFlagBits) !=
+                   SkToBool(kHWAntialias_StateBit & fCurrDrawState.fFlagBits) !=
                    fHWAAState.fMSAAEnabled) {
             if (fHWAAState.fMSAAEnabled) {
                 GL_CALL(Disable(GR_GL_MULTISAMPLE));