Add cc/paint to ui/touch_selection deps.

cc::PaintFlags is used when drawing TouchSelectionMagnifierAura's border
and shadows, but the header wasn't included when the magnifier was
initially implemented. Add the include and update deps accordingly.

Bug: b:295261171
Change-Id: I4df284e32608f4caae12a345b5af668b46a5ec3f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4856086
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Michelle Chen <michellegc@google.com>
Reviewed-by: Sunny Sachanandani <sunnyps@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1196400}