Disable MessagePumpLibeventTest.TestWatchingFromBadThread on Chrome OS

base/message_loop/message_pump_libevent_unittest.cc

Index: base/message_loop/message_pump_libevent_unittest.cc
diff --git a/base/message_loop/message_pump_libevent_unittest.cc b/base/message_loop/message_pump_libevent_unittest.cc
index 65d721727284f35cfdc3ad621c63ddb5fa51e9e7..7d796dff8763cfee5ddc6f906b4d95bd1b1d8631 100644
--- a/base/message_loop/message_pump_libevent_unittest.cc
+++ b/base/message_loop/message_pump_libevent_unittest.cc
@@ -77,7 +77,13 @@ class StupidWatcher : public MessagePumpLibevent::Watcher {
 
 // Test to make sure that we catch calling WatchFileDescriptor off of the
 // wrong thread.
-TEST_F(MessagePumpLibeventTest, TestWatchingFromBadThread) {
+#if defined(OS_CHROMEOS)
+// Flaky on Chrome OS: crbug.com/138845.
+#define MAYBE_TestWatchingFromBadThread DISABLED_TestWatchingFromBadThread
+#else
+#define MAYBE_TestWatchingFromBadThread TestWatchingFromBadThread
+#endif
+TEST_F(MessagePumpLibeventTest, MAYBE_TestWatchingFromBadThread) {
   MessagePumpLibevent::FileDescriptorWatcher watcher;
   StupidWatcher delegate;