Add Page.stopLoading to devtools and --timeout switch to headless_shell

headless/app/headless_shell_switches.cc

 // Copyright 2016 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 "headless/app/headless_shell_switches.h"
 
 namespace headless {
 namespace switches {
 
 // Instructs headless_shell to cause network fetches to complete in order of
@@ skipping 17 matching lines @@
 // so exposing it too widely can be a security risk.
 const char kRemoteDebuggingAddress[] = "remote-debugging-address";
 
 // Runs a read-eval-print loop that allows the user to evaluate Javascript
 // expressions.
 const char kRepl[] = "repl";
 
 // Save a screenshot of the loaded page.
 const char kScreenshot[] = "screenshot";
 
+// Issues a stop after the specified number of milliseconds.  This cancels all
+// navigation and causes the DOMContentLoaded event to fire.
+const char kTimeout[] = "timeout";
+
 // Sets the GL implementation to use. Use a blank string to disable GL
 // rendering.
 const char kUseGL[] = "use-gl";
 
 // Directory where the browser stores the user profile.
 const char kUserDataDir[] = "user-data-dir";
 
 // If set the system waits the specified number of virtual milliseconds before
 // deeming the page to be ready.  For determinism virtual time does not advance
 // while there are pending network fetches (i.e no timers will fire). Once all
 // network fetches have completed, timers fire and if the system runs out of
 // virtual time is fastforwarded so the next timer fires immediatley, until the
 // specified virtual time budget is exhausted.
 const char kVirtualTimeBudget[] = "virtual-time-budget";
 
 // Sets the initial window size. Provided as string in the format "800x600".
 const char kWindowSize[] = "window-size";
 
 }  // namespace switches
 }  // namespace headless