ScrollbarStyles contains values of overflow, (over)scroll-behavior, etc.
The only one which is marginally related to scroll _bars_ is overflow, which can
be used to hide scrollbar (by making an element not scrollable) or enforce the
scrollbar to display.
It makes more sense to be called ScrollStyles as it's mainly concerning behavior
of scrolling, not scrollbars. Also, with the addition of scrollbar width
properties, the current name can be confusing.
* Tidy RestyleManager::ContentStateChanged
* Convert UndisplayedMap to a typed hashtable
* Cleanup infallible or unchecked nsCSSFrameConstructor methods
Tag #1375
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.
