commit f5a240b69f54097ebec24fddb5422e191a2c997d
author Brian Liu Xu <brx@microsoft.com> Wed Aug 21 21:40:37 2019
committer Commit Bot <commit-bot@chromium.org> Wed Aug 21 21:40:37 2019
tree f14293ee4047261dad8dfe840c1053688fe28af2
parent 5115dce687c7d97d069494c6780ffabf4c8cb03b

Fix Views bug causing layers to get stuck at 100% DPI pixel boundaries

This patch fixes logic for snapping layers to physical pixel boundaries,
when pixel canvas is not enabled, by allowing the subpixel offset to be
dynamically computed. Previously, layers could get stuck at 100% DPI
pixel boundaries (making some UI blurry on platforms where fractional
scale factors are used, e.g. Windows), as once an explicit value was
set, the offset would no longer be dynamically computed.

This patch
 - Updates SnapLayerToPixelBoundary to stop View from setting explicit
   subpixel offsets for non-pixel-canvas platforms so that they may be
   auto computed.
 - Updates view_unittest.

Bug: 992730
Change-Id: I8e8c87107f13157e92f125bcfb281226ebc6c422
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1761301
Reviewed-by: Malay Keshav <malaykeshav@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Brian Liu Xu <brx@microsoft.com>
Auto-Submit: Brian Liu Xu <brx@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#689171}