Replace "http" etc with the url_constants version. This was a previous TODO for webplugin_proxy....

chrome/browser/prerender/prerender_contents.cc

 // Copyright (c) 2011 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/prerender/prerender_contents.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/process_util.h"
@@ skipping 645 matching lines @@
        it != urls.end(); ++it) {
     if (it->icon_type == FaviconURL::FAVICON) {
       icon_url_ = it->icon_url;
       VLOG(1) << icon_url_;
       return;
     }
   }
 }
 
 bool PrerenderContents::AddAliasURL(const GURL& url) {
-  if (!url.SchemeIs("http")) {
-    if (url.SchemeIs("https"))
+  if (!url.SchemeIs(chrome::kHttpScheme)) {
+    if (url.SchemeIs(chrome::kHttpsScheme))
       Destroy(FINAL_STATUS_HTTPS);
     else
       Destroy(FINAL_STATUS_UNSUPPORTED_SCHEME);
     return false;
   }
   if (prerender_manager_->HasRecentlyBeenNavigatedTo(url)) {
     Destroy(FINAL_STATUS_RECENTLY_VISITED);
     return false;
   }
   alias_urls_.push_back(url);
@@ skipping 147 matching lines @@
   }
   return render_view_host_;
 }
 
 void PrerenderContents::CommitHistory(TabContents* tc) {
   if (tab_contents_delegate_.get())
     tab_contents_delegate_->CommitHistory(tc);
 }
 
 }  // namespace prerender