Disable TestGpuProcess test on Thread Sanitizer

Tbr: avi@chromium.org

Bug: 1127374
Change-Id: If9430b80dc5d13d2e9e71fd52c4b7730448ccee8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2404806
Commit-Queue: sebsg <sebsg@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Chan Li <chanli@chromium.org>
Auto-Submit: sebsg <sebsg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#806229}

content/browser/power_monitor_browsertest.cc

@@ -261,8 +261,13 @@ IN_PROC_BROWSER_TEST_F(PowerMonitorTest, TestUtilityProcess) {
   // Verify utility process on_battery_power changed to false.
   VerifyPowerStateInChildProcess(power_monitor_utility.get(), false);
 }
-
-IN_PROC_BROWSER_TEST_F(PowerMonitorTest, TestGpuProcess) {
+// This flakes on Linux TSan: http://crbug.com/1127374
+#if defined(THREAD_SANITIZER)
+#define MAYBE_TestGpuProcess DISABLED_TestGpuProcess
+#else
+#define MAYBE_TestGpuProcess TestGpuProcess
+#endif
+IN_PROC_BROWSER_TEST_F(PowerMonitorTest, MAYBE_TestGpuProcess) {
   // As gpu process is started automatically during the setup period of browser
   // test suite, it may have already started and bound PowerMonitor interface to
   // Device Service before execution of this TestGpuProcess test. So here we