Cleanup: Move kChromeDevToolsScheme constant into content namespace.

content/browser/webui/url_data_manager_backend.cc

Index: content/browser/webui/url_data_manager_backend.cc
diff --git a/content/browser/webui/url_data_manager_backend.cc b/content/browser/webui/url_data_manager_backend.cc
index 35ea0c163d610b511fb86e7d1e70fc97f493cd7d..9313d9faebb26a3a48e089826648d9d35fa50d9d 100644
--- a/content/browser/webui/url_data_manager_backend.cc
+++ b/content/browser/webui/url_data_manager_backend.cc
@@ -64,8 +64,7 @@ bool SchemeIsInSchemes(const std::string& scheme,
 // Returns whether |url| passes some sanity checks and is a valid GURL.
 bool CheckURLIsValid(const GURL& url) {
   std::vector<std::string> additional_schemes;
-  DCHECK(url.SchemeIs(chrome::kChromeDevToolsScheme) ||
-         url.SchemeIs(kChromeUIScheme) ||
+  DCHECK(url.SchemeIs(kChromeDevToolsScheme) || url.SchemeIs(kChromeUIScheme) ||
          (GetContentClient()->browser()->GetAdditionalWebUISchemes(
               &additional_schemes),
           SchemeIsInSchemes(url.scheme(), additional_schemes)));