Disable ChromeScreenshotGrabberTest.TakeScreenshot as it's flaky on Chrome OS

chrome/browser/ui/ash/chrome_screenshot_grabber_unittest.cc

 // Copyright 2013 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 "chrome/browser/ui/ash/chrome_screenshot_grabber.h"
 
 #include "ash/common/accelerators/accelerator_controller.h"
 #include "ash/shell.h"
 #include "ash/test/ash_test_base.h"
 #include "base/bind.h"
@@ skipping 84 matching lines @@
   bool screenshot_complete_;
   ScreenshotGrabberObserver::Result screenshot_result_;
   std::unique_ptr<ChromeScreenshotGrabber> chrome_screenshot_grabber_;
   base::FilePath screenshot_path_;
   scoped_refptr<content::MessageLoopRunner> message_loop_runner_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ChromeScreenshotGrabberTest);
 };
 
-TEST_F(ChromeScreenshotGrabberTest, TakeScreenshot) {
+// Flaky on "Linux ChromiumOS Tests (dbg)(1)". See http://crbug.com/645864.
+TEST_F(ChromeScreenshotGrabberTest, DISABLED_TakeScreenshot) {
   // Note that within the test framework the LoginState object will always
   // claim that the user did log in.
   ASSERT_FALSE(chromeos::LoginState::IsInitialized());
   chromeos::LoginState::Initialize();
   chromeos::ScopedUserManagerEnabler scoped_enabler(
       new chromeos::MockUserManager());
   base::ScopedTempDir directory;
   ASSERT_TRUE(directory.CreateUniqueTempDir());
   EXPECT_TRUE(chrome_screenshot_grabber()->CanTakeScreenshot());
 
@@ skipping 14 matching lines @@
   EXPECT_EQ(ScreenshotGrabberObserver::SCREENSHOT_SUCCESS, screenshot_result_);
 
   if (ScreenshotGrabberObserver::SCREENSHOT_SUCCESS == screenshot_result_)
     EXPECT_TRUE(base::PathExists(screenshot_path_));
 
   chromeos::LoginState::Shutdown();
 }
 
 }  // namespace test
 }  // namespace ash