Fix a bug in SkTextBox.

When checking to see if the line of text is beyond the bottom of
the textbox, compare with the bottom, rather than the height (bottom
- top). Prior to this change, text in the bottom of a textbox could
be clipped out.

BUG=https://code.google.com/p/skia/issues/detail?id=1250

Review URL: https://codereview.chromium.org/13856017

git-svn-id: http://skia.googlecode.com/svn/trunk@8838 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed