Fix content_width in IncrementalTextLayout.  This fixes the side-to-side scrolling of text with caret motion in test cases.
Fix content_width in IncrementalTextLayout.  This fixes the side-to-side
scrolling of text with caret motion in test cases.

Alwnikrotikz/pyglet,mpasternak/michaldtz-fix-552,google-code-export/pyglet,gdkar/pyglet,Austin503/pyglet,qbektrix/pyglet,shaileshgoogler/pyglet,cledio66/pyglet,xshotD/pyglet,mpasternak/pyglet-fix-issue-518-522,mpasternak/michaldtz-fixes-518-522,kmonsoor/pyglet,mpasternak/pyglet-fix-issue-518-522,xshotD/pyglet,Austin503/pyglet,Alwnikrotikz/pyglet,gdkar/pyglet,mpasternak/pyglet-fix-issue-518-522,qbektrix/pyglet,cledio66/pyglet,mpasternak/pyglet-fix-issue-552,google-code-export/pyglet,kmonsoor/pyglet,gdkar/pyglet,mpasternak/michaldtz-fixes-518-522,odyaka341/pyglet,gdkar/pyglet,xshotD/pyglet,Austin503/pyglet,mpasternak/pyglet-fix-issue-518-522,xshotD/pyglet,mpasternak/michaldtz-fixes-518-522,arifgursel/pyglet,arifgursel/pyglet,cledio66/pyglet,arifgursel/pyglet,qbektrix/pyglet,google-code-export/pyglet,qbektrix/pyglet,Austin503/pyglet,odyaka341/pyglet,cledio66/pyglet,kmonsoor/pyglet,Alwnikrotikz/pyglet,mpasternak/michaldtz-fix-552,google-code-export/pyglet,Austin503/pyglet,shaileshgoogler/pyglet,shaileshgoogler/pyglet,mpasternak/michaldtz-fix-552,cledio66/pyglet,mpasternak/michaldtz-fixes-518-522,odyaka341/pyglet,Alwnikrotikz/pyglet,mpasternak/michaldtz-fix-552,odyaka341/pyglet,arifgursel/pyglet,arifgursel/pyglet,mpasternak/pyglet-fix-issue-552,Alwnikrotikz/pyglet,xshotD/pyglet,kmonsoor/pyglet,kmonsoor/pyglet,shaileshgoogler/pyglet,mpasternak/pyglet-fix-issue-552,gdkar/pyglet,mpasternak/pyglet-fix-issue-552,odyaka341/pyglet,shaileshgoogler/pyglet,qbektrix/pyglet,google-code-export/pyglet