Compensate for page scale in animated scrolls

When the user zooms into the page, scrolling should be proportionally
reduced so the page appears to move at the same rate. This is currently
done for various kinds of scrolling.

An animated scroll that updates an existing scroll animation simply
adjusts the animation curve's target delta. However, this path forgot
to adjust by the page scale factor like the "new animation" and "non-
animated" paths. This CL simply adds that in.

Bug: 610021
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.android:android_optional_gpu_tests_rel
Change-Id: Ic1a6421131915ad739d39ad3ef36792dd3be53aa
Reviewed-on: https://chromium-review.googlesource.com/788134
Reviewed-by: Robert Flack <flackr@chromium.org>
Commit-Queue: David Bokan <bokan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#519456}
2 files changed