Disable PPAPINaClGLibcTest.Graphics2D_FlushOffscreenUpdate on Windows

chrome/test/ppapi/ppapi_browsertest.cc

Index: chrome/test/ppapi/ppapi_browsertest.cc
diff --git a/chrome/test/ppapi/ppapi_browsertest.cc b/chrome/test/ppapi/ppapi_browsertest.cc
index fe9cef5dd931449c097cd3bf19772ffd578f9468..955e9877c050766eaf48e016763b2802322c756c 100644
--- a/chrome/test/ppapi/ppapi_browsertest.cc
+++ b/chrome/test/ppapi/ppapi_browsertest.cc
@@ -276,6 +276,14 @@ IN_PROC_BROWSER_TEST_F(OutOfProcessPPAPITest,
   RunTest("Instance_ExecuteScriptAtInstanceShutdown");
 }
 
+#if defined(OS_WIN)
+// Flaky on Win7. http://crbug.com/320548
+#define MAYBE_Graphics2D_FlushOffscreenUpdate \
+    DISABLED_Graphics2D_FlushOffscreenUpdate
+#else
+#define MAYBE_Graphics2D_FlushOffscreenUpdate Graphics2D_FlushOffscreenUpdate
+#endif
+
 TEST_PPAPI_IN_PROCESS(Graphics2D)
 TEST_PPAPI_OUT_OF_PROCESS(Graphics2D)
 // Graphics2D_Dev isn't supported in NaCl, only test the other interfaces
@@ -289,7 +297,7 @@ TEST_PPAPI_NACL(Graphics2D_Paint)
 TEST_PPAPI_NACL(Graphics2D_Scroll)
 TEST_PPAPI_NACL(Graphics2D_Replace)
 TEST_PPAPI_NACL(Graphics2D_Flush)
-TEST_PPAPI_NACL(Graphics2D_FlushOffscreenUpdate)
+TEST_PPAPI_NACL(MAYBE_Graphics2D_FlushOffscreenUpdate)
 TEST_PPAPI_NACL(Graphics2D_BindNull)
 
 #if defined(OS_WIN)