XUL trees can contain -moz-appearance widgets whose rendering depends on window focus. At the moment, nothing invalidates the XUL tree when the window focus changes, so those widgets can look incorrect.

Bug 1493789 is going to add another case of this, where the shade of gray of inactive sidebar selections changes a slight amount depending on the window focus state.

It think the easiest way to fix this is to just make the entire XUL tree repaint every time its containing window changes focus.

Backed out changeset 53c16c65827a (bug 1644468) for Mochitest failures in checkouts/gecko/layout/painting/nsDisplayListInvalidation.h. CLOSED TREE

Log:
https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=305959440&repo=autoland&lineNumber=2270

https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=305959485&repo=autoland&lineNumber=1034

https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=305957402&repo=autoland&lineNumber=1244

Push with failures:
https://treeherder.mozilla.org/#/jobs?repo=autoland&group_state=expanded&revision=53c16c65827af9ac2c95e057a2723709688f1178

Backout:
https://hg.mozilla.org/integration/autoland/rev/29082233b33dc411ca5740c22948ee53044b1c5b

Wow, that's a footgun and a half. The call to nsDisplayItemGenericImageGeometry::UpdateDrawResult(this, result); in Paint() needs to be updated to call nsDisplayTreeBodyGeometry::UpdateDrawResult instead. UpdateDrawResult a generic static method that happily casts FrameLayerBuilder::GetMostRecentGeometry(aItem) to whatever concrete class it's called on.

I'm really happy we have ASAN tests! They pointed right at the culprit. The crash stacks in the other tests were much less helpful.

Also caused: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=305970248&repo=autoland&lineNumber=1386
https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=305975265&repo=autoland&lineNumber=1056

Backed out for perma failures.

Push with failure: https://treeherder.mozilla.org/#/jobs?repo=autoland&resultStatus=pending%2Crunning%2Csuccess%2Ctestfailed%2Cbusted%2Cexception&searchStr=windows%2C10%2Cx64%2Casan%2Cmochitests%2Cwithout%2Ce10s%2Ctest-windows10-64-asan%2Fopt-mochitest-a11y-1proc%2Cm-1proc%28a11y%29&revision=6bc479713c3c5de3f2a38c1dd09dc348cb2336f4&selectedTaskRun=BYr1Ubm2SLOJNtMtxQDy8Q.0

Logs:
https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=306000428&repo=autoland&lineNumber=1176

https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=306003349&repo=autoland&lineNumber=1886

Backout: https://hg.mozilla.org/integration/autoland/rev/bc9ef959da6b1f5039c6f29b50315ff3495e218e

I got the base class wrong :(

I wish there were more compile time checks in this code.

https://hg.mozilla.org/mozilla-central/rev/ddbf6052a717