cc: Fix ScrollbarLayer overflow

During clamping to the max texture size, if scaling saturates
scaled_bounds width or height to MAX_INT, then we weren't clamping
correctly for bounds().height() > width.

BUG=541528
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1402653002

Cr-Commit-Position: refs/heads/master@{#353633}
2 files changed