Revert 180055: Very likely caused http://crbug.com/173885

content/public/common/url_constants.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 "content/public/common/url_constants.h"
 
 #include "content/common/savable_url_schemes.h"
 #include "googleurl/src/gurl.h"
 
 namespace chrome {
@@ skipping 24 matching lines @@
 const char kChromeUIAppCacheInternalsHost[] = "appcache-internals";
 const char kChromeUIBlobInternalsHost[] = "blob-internals";
 const char kChromeUIBrowserCrashHost[] = "inducebrowsercrashforrealz";
 const char kChromeUIDevToolsHost[] = "devtools";
 const char kChromeUIGpuHost[] = "gpu";
 const char kChromeUIHistogramHost[] = "histograms";
 const char kChromeUIMediaInternalsHost[] = "media-internals";
 const char kChromeUINetworkViewCacheHost[] = "view-http-cache";
 const char kChromeUIResourcesHost[] = "resources";
 const char kChromeUITcmallocHost[] = "tcmalloc";
-const char kChromeUITracingHost[] = "tracing";
 const char kChromeUIWebRTCInternalsHost[] = "webrtc-internals";
 
 const char kChromeUICrashURL[] = "chrome://crash";
 const char kChromeUIGpuCleanURL[] = "chrome://gpuclean";
 const char kChromeUIGpuCrashURL[] = "chrome://gpucrash";
 const char kChromeUIGpuHangURL[] = "chrome://gpuhang";
 const char kChromeUIHangURL[] = "chrome://hang";
 const char kChromeUIKillURL[] = "chrome://kill";
 const char kChromeUIPpapiFlashCrashURL[] = "chrome://ppapiflashcrash";
 const char kChromeUIPpapiFlashHangURL[] = "chrome://ppapiflashhang";
@@ skipping 23 matching lines @@
 bool HasWebUIScheme(const GURL& url) {
   return
 #if !defined(OS_IOS)
          url.SchemeIs(chrome::kChromeDevToolsScheme) ||
          url.SchemeIs(chrome::kChromeInternalScheme) ||
 #endif
          url.SchemeIs(chrome::kChromeUIScheme);
 }
 
 }  // namespace content