This updates our behavior for computed DOM styling to no longer return
null on elements that have no display, but return a 0-length (empty)
style instead and don't throw. For this we stop looking at having a
presentation for the style and just look at the document instead.
This resolves#1219
This also addresses clearing of document dependent JS slots which might
get out of sync with innerWindow navigation; relevant comments added.
This resolves#1253
Tag #1052 (backout).
Backed out for creating issues like #1191 and other issue-less problems
with e.g. losing the caret from text boxes. Of note: this was also
backed out from m-c for similar reasons in Bug 1332433.
This fixes#1191.
This reverts commit 3424afccaebc71c4acd4fa9eadf519c408c5965b.
This creates a number of stubs and leaves some surrounding code that may be irrelevant (eg. recorded time stamps, status variables).
Stub resolution/removal should be a follow-up to this.
