Fix TabLayout text size issue

Some new measurement code in N seems to have
tickled a recursion exit check in TabLayout's
text size setting code when it's not required.

This CL fixes the check by checking against
the available space for the text, rather than
the existing Layout's width.

BUG: 27923340
Change-Id: I1be8c489488fc96fc3802b45c525b5fa6cae337d
1 file changed