Move RemoveChars, ReplaceChars, TrimString, and TruncateUTF8ToByteSize to base namespace.

chrome/browser/guestview/adview/adview_guest.cc

Index: chrome/browser/guestview/adview/adview_guest.cc
diff --git a/chrome/browser/guestview/adview/adview_guest.cc b/chrome/browser/guestview/adview/adview_guest.cc
index 44acbd9eeeee7782144d5c040415f1e90ae61255..0cdeccd7a412b122e2093de24136f3d7d083712b 100644
--- a/chrome/browser/guestview/adview/adview_guest.cc
+++ b/chrome/browser/guestview/adview/adview_guest.cc
@@ -65,7 +65,7 @@ void AdViewGuest::DidFailProvisionalLoad(
     content::RenderViewHost* render_view_host) {
   // Translate the |error_code| into an error string.
   std::string error_type;
-  RemoveChars(net::ErrorToString(error_code), "net::", &error_type);
+  base::RemoveChars(net::ErrorToString(error_code), "net::", &error_type);
 
   scoped_ptr<DictionaryValue> args(new DictionaryValue());
   args->SetBoolean(guestview::kIsTopLevel, is_main_frame);