tree 32642fa85639ac49bd21b28378671493e96efc87
parent 02eedde6834bff9d72066339bf9df62911e4df3e
author Harry Cutts <hcutts@chromium.org> 1653691663 -0700
committer Chromeos LUCI <chromeos-scoped@luci-project-accounts.iam.gserviceaccount.com> 1654046038 +0000

mouse: emulate scrolling with left+right pressed

Many mice and trackballs without scroll wheels also lack a middle
button, meaning that they can't activate scroll wheel emulation.
Activating it when the left and right buttons are held simultaneously
improves the user experience with such devices.

BUG=b:234160991
TEST=With Logitech Trackman Marble (which has no middle button), check
     scrolling emulation works. With 3M Ergonomic Mouse (which has a
     middle button but no wheel) check that middle-click still works.

Change-Id: Iffe1de3503e97562952ff451549cd4118abf1f89
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/gestures/+/3673134
Tested-by: Harry Cutts <hcutts@chromium.org>
Reviewed-by: Sean O'Brien <seobrien@chromium.org>
Commit-Queue: Harry Cutts <hcutts@chromium.org>