Upstream commit broke our Win7 tests due to using ::GetDpiForMonitor which is only available on Win8 and newer machines. To unblock, we simply disabled that code and returned a default value. We should restore the functionality for newer machines.

It's available from win8.1 for which the NTDDI_VERSION macro has the value NTDDI_WINBLUE. Maybe we want a runtime check instead, then we can look at this. I found no equivalent in libwebrtc, the closest is this explicit check.

(In reply to Andreas Pehrson [:pehrsons] from comment #1)

It's available from win8.1 for which the NTDDI_VERSION macro has the value NTDDI_WINBLUE. Maybe we want a runtime check instead, then we can look at this. I found no equivalent in libwebrtc, the closest is this explicit check.

+1

A run time check would be great for binary portability.

Backed out for causing windows crashes.

Push with failures: https://treeherder.mozilla.org/jobs?repo=autoland&group_state=expanded&resultStatus=testfailed%2Cbusted%2Cexception&revision=1877c1e6db6f8a23c52ab9238c7f62d0b696f0ce&searchStr=windows&selectedTaskRun=dqNtHfUxSfKJVyF_vsD96g.0

Failure logs:

• https://treeherder.mozilla.org/logviewer?job_id=420013777&repo=autoland
• https://treeherder.mozilla.org/logviewer?job_id=420013759&repo=autoland
• https://treeherder.mozilla.org/logviewer?job_id=420012387&repo=autoland
• https://treeherder.mozilla.org/logviewer?job_id=420012373&repo=autoland

Backout link: https://hg.mozilla.org/integration/autoland/rev/bdf8893a3dfdac6fe0ad445625a24e6d18e89fda

Investigating.

https://hg.mozilla.org/mozilla-central/rev/efb1631077da