Make GTMUILocalizer's IBOutlet fields @protected.                                

Private fields are turned into hidden symbols with the 64bit runtime,            
so classes that are not in the same dylib / framework as GTMUILocalizer cannot   
access these fields otherwise.

This is for http://crbug.com/190508

DELTA=2  (1 added, 0 deleted, 1 changed)

git-svn-id: http://google-toolbox-for-mac.googlecode.com/svn/trunk@608 7dc7ac4e-7543-0410-b95c-c1676fc8e2a3