_screenshotOSX() ran an osascript to look up the frontmost window's id before
capturing. Sending that Apple Event requires the macOS Automation permission,
which CI workers don't grant, so it timed out (AppleEvent timed out, -1712) and
the suite expanded to consume its whole timeout budget. This is the root cause
behind the long-standing macOS mozscreenshots skips (see bug 1554821).
The window id was never actually used by the capture (screencapture already grabs
the whole screen), so drop the osascript step and call screencapture -x directly,
matching what the Linux and Windows paths do.
Drop the macOS skips on browser_primaryUI.js, browser_controlCenter.js and
browser_preferences.js now that this timeout is fixed. The remaining skips only
covered Intel macs, where the screenshots suite is no longer scheduled.
browser_screenshots_cropping.js compares canvas-cropped images against reference
PNGs; on Apple Silicon the cropped output differs from the references by a small
number of edge pixels. Skip it on macosx1500-aarch64 for now; this is independent
of the capture mechanism and was never exercised while the suite was disabled.
Differential Revision: https://phabricator.services.mozilla.com/D309409
Florian Quèze
0d95ba0f36