947daa8d85
This matches the spec and Chrome, and seems to bring us closer to Edge and WebKit as well. It also matches our own behavior for addRange(), which was changed in bug 1341137. For collapse and selectAllChildren, we match the tests and browsers, but the spec is incorrect at the time of this writing: https://github.com/w3c/selection-api/pull/86 The removeAllRanges test hadn't been updated for the spec change. MozReview-Commit-ID: DTK8283k5IP