Update the line break mode to use the updated constant, NSLineBreakByClipping, instead of UILineBreakModeClip.

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

git-svn-id: http://google-toolbox-for-mac.googlecode.com/svn/trunk@626 7dc7ac4e-7543-0410-b95c-c1676fc8e2a3