Disable flaky test BackgroundTracingThrottleTimeElapsed on Linux

chrome/browser/tracing/chrome_tracing_delegate_browsertest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <utility>
 
 #include "base/base_switches.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "build/build_config.h"
@@ skipping 133 matching lines @@
   const base::Time last_upload_time = base::Time::FromInternalValue(
       local_state->GetInt64(prefs::kBackgroundTracingLastUpload));
   EXPECT_FALSE(last_upload_time.is_null());
 
   // We should not be able to start a new reactive scenario immediately after
   // a previous one gets uploaded.
   EXPECT_FALSE(StartPreemptiveScenario(
       base::Closure(), content::BackgroundTracingManager::NO_DATA_FILTERING));
 }
 
+// Flaky on Linux. See https://crbug.com/723933.
+#if defined(OS_LINUX)
+#define MAYBE_BackgroundTracingThrottleTimeElapsed \
+  DISABLED_BackgroundTracingThrottleTimeElapsed
+#else
+#define MAYBE_BackgroundTracingThrottleTimeElapsed \
+  BackgroundTracingThrottleTimeElapsed
+#endif
 IN_PROC_BROWSER_TEST_F(ChromeTracingDelegateBrowserTest,
-                       BackgroundTracingThrottleTimeElapsed) {
+                       MAYBE_BackgroundTracingThrottleTimeElapsed) {
   base::RunLoop wait_for_upload;
 
   EXPECT_TRUE(StartPreemptiveScenario(
       wait_for_upload.QuitClosure(),
       content::BackgroundTracingManager::NO_DATA_FILTERING));
 
   TriggerPreemptiveScenario(base::Closure());
 
   wait_for_upload.Run();
 
@@ skipping 126 matching lines @@
 
 IN_PROC_BROWSER_TEST_F(ChromeTracingDelegateBrowserTestOnStartup,
                        StartupTracingThrottle) {
   // The startup scenario should *not* be started, since not enough
   // time has elapsed since the last upload (set in the PRE_ above).
   EXPECT_FALSE(
       content::BackgroundTracingManager::GetInstance()->HasActiveScenario());
 }
 
 }  // namespace