commit da4040d2068fe0cf9674a16a4d4474b4346b51b5
author Thomas Lukaszewicz <tluk@chromium.org> Mon Mar 10 17:54:13 2025
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Mon Mar 10 17:54:13 2025
tree 32ca3919e52958d50fd355ab2b2ee2dc6c357331
parent 96df931a7ef2aa52f2899549763d27fde043afd2

[aura] Correctly adjust size for GetWindowMask() calculation

This CL ensures HWND size is correctly adjusted by window_enlargement_
in DesktopWindowTreeHostWin::GetWindowMask().

This CL also updates code in DesktopWindowTreeHostWin::GetWindowMask()
that was getting bounds from the hwnd message handler rather than using
the size passed directly from HWNDMessageHandler::ResetWindowRegion().
Logically this is not correct and the mask should be applied with
respect to the hwnd size passed into GetWindowMask().

window_enlargement_ was introduced in 2013 to address graphical
glitches reported on specific AMD graphics drivers for windows smaller
than 64x64. The resulting fix enlarged the backing hwnd of transparent
widgets to 64x64 if required, capturing the offset in
window_enlargement_, resizing as appropriate when interacting with
the hwnd_message_handler.

This specific fix is likely no longer relevant and code can be
simplified by removing this completely.

Before:
https://screenshot.googleplex.com/7R8wM2esPSEdKj5.png

After:
https://screenshot.googleplex.com/7jZ6sepEUXVKrRi.png

Bug: 399737950, 401996981
Change-Id: Ie7b6a7b429d09912bc5ffc9e465a4dc18772f9e9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6337512
Reviewed-by: Keren Zhu <kerenzhu@chromium.org>
Commit-Queue: Tom Lukaszewicz <tluk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1430350}