platform apps: Disables history.pushState/replaceState in platform_app.js.

chrome/renderer/content_settings_observer.cc

 // Copyright (c) 2012 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/renderer/content_settings_observer.h"
 
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "chrome/common/render_messages.h"
 #include "content/public/common/url_constants.h"
@@ skipping 436 matching lines @@
     }
   }
 #endif
   return allowed;
 }
 
 bool ContentSettingsObserver::allowMutationEvents(bool default_value) {
   return IsPlatformApp() ? false : default_value;
 }
 
-bool ContentSettingsObserver::allowPushState() {
-  return !IsPlatformApp();
-}
-
 static void SendInsecureContentSignal(int signal) {
   UMA_HISTOGRAM_ENUMERATION("SSL.InsecureContent", signal,
                             INSECURE_CONTENT_NUM_EVENTS);
 }
 
 bool ContentSettingsObserver::allowDisplayingInsecureContent(
     bool allowed_per_settings,
     const blink::WebSecurityOrigin& origin,
     const blink::WebURL& resource_url) {
   SendInsecureContentSignal(INSECURE_CONTENT_DISPLAY);
@@ skipping 244 matching lines @@
 
   // If the scheme is file:, an empty file name indicates a directory listing,
   // which requires JavaScript to function properly.
   if (EqualsASCII(origin.protocol(), url::kFileScheme)) {
     return document_url.SchemeIs(url::kFileScheme) &&
            document_url.ExtractFileName().empty();
   }
 
   return false;
 }