Fixes issue with Allman BreakBeforeBraces for Objective C @interface

Before:
        @interface BSApplicationController () {
    @private
      id _extraIvar;
    }
    @end

After:
    @interface BSApplicationController ()
    {
    @private
      id _extraIvar;
    }
    @end



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@207849 91177308-0d34-0410-b5e6-96231b3b80d8