Disable all the browser_tests that are flaking more than 5% of the time on trybots.

chrome/browser/chromeos/extensions/virtual_keyboard_browsertest.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/chromeos/extensions/virtual_keyboard_browsertest.h"
 
 #include <vector>
 
 #include "ash/shell.h"
@@ skipping 125 matching lines @@
 IN_PROC_BROWSER_TEST_F(VirtualKeyboardBrowserTest, DISABLED_ControlKeysTest) {
   RunTest(base::FilePath(FILE_PATH_LITERAL("control_keys_test.js")),
           VirtualKeyboardBrowserTestConfig());
 }
 
 IN_PROC_BROWSER_TEST_F(VirtualKeyboardBrowserTest, HideKeyboardKeyTest) {
   RunTest(base::FilePath(FILE_PATH_LITERAL("hide_keyboard_key_test.js")),
           VirtualKeyboardBrowserTestConfig());
 }
 
-IN_PROC_BROWSER_TEST_F(VirtualKeyboardBrowserTest, KeysetTransitionTest) {
+// http://crbug.com/396326
+IN_PROC_BROWSER_TEST_F(VirtualKeyboardBrowserTest,
+                       DISABLED_KeysetTransitionTest) {
   RunTest(base::FilePath(FILE_PATH_LITERAL("keyset_transition_test.js")),
           VirtualKeyboardBrowserTestConfig());
 }
 
 // Fails when enabling Object.observe. See http://crbug.com/370004
 #if defined(OS_CHROMEOS)
 #define MAYBE_IsKeyboardLoaded DISABLED_IsKeyboardLoaded
 #else
 #define MAYBE_IsKeyboardLoaded IsKeyboardLoaded
 #endif
@@ skipping 40 matching lines @@
   bool success = false;
   EXPECT_TRUE(content::ExecuteScriptAndExtractBool(
       browser_rvh,
       "success ? verifyInput('a') : waitForInput('a');",
       &success));
   ASSERT_TRUE(success);
 }
 
 // TODO(kevers|rsadam|bshe):  Add UI tests for remaining virtual keyboard
 // functionality.