|NS_ConvertUTF8toUCS2| |NS_ConvertASCIItoUCS2| |NS_ConvertUCS2toUTF8| |ns[C]LiteralString| |ns[C]PromiseFlatString| to explicit |get()|. Add |get()| to |nsString|, remove implicit conversion operators where possible, add NS_WARNING where not (yet!). Bug=53057, r=alecf, sr=scc git-svn-id: svn://10.0.0.236/trunk@88947 18797224-902f-48f8-a5cc-f745e15eee43