Disable all the tests that are flaking more than 5% on ChromeOS builders.

content/browser/service_worker/service_worker_browsertest.cc

 // Copyright 2014 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 "base/bind.h"
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/browser/fileapi/chrome_blob_storage_context.h"
@@ skipping 724 matching lines @@
 static int CountRenderProcessHosts() {
   int result = 0;
   for (RenderProcessHost::iterator iter(RenderProcessHost::AllHostsIterator());
        !iter.IsAtEnd();
        iter.Advance()) {
     result++;
   }
   return result;
 }
 
-// Crashes on Android: http://crbug.com/387045
-#if defined(OS_ANDROID)
+// Crashes on Android and flakes on CrOS: http://crbug.com/387045
+#if defined(OS_ANDROID) || defined(OS_CHROMEOS)
 #define MAYBE_Registration DISABLED_Registration
 #else
 #define MAYBE_Registration Registration
 #endif
 IN_PROC_BROWSER_TEST_F(ServiceWorkerBlackBoxBrowserTest, MAYBE_Registration) {
   // Close the only window to be sure we're not re-using its RenderProcessHost.
   shell()->Close();
   EXPECT_EQ(0, CountRenderProcessHosts());
 
   const std::string kWorkerUrl = "/service_worker/fetch_event.js";
@@ skipping 64 matching lines @@
         base::Bind(&ServiceWorkerBlackBoxBrowserTest::FindRegistrationOnIO,
                    this,
                    embedded_test_server()->GetURL("/service_worker/empty.html"),
                    &status,
                    &script_url));
     EXPECT_EQ(SERVICE_WORKER_ERROR_NOT_FOUND, status);
   }
 }
 
 }  // namespace content