Our currently ad-hoc method of tracking element references is basically
a process-wide map, rather than grouping elements according to their
browsing context groups. This prevents us from recognizing when an
element reference is invalid due to its browsing context having been
closed.
This implements the WebDriver spec concept of element references grouped
according to their browsing context groups.
This patch is a bit noisy because we now need to plumb the current BC
through to the element reference AOs.
There are many WPT subtests which validate how we behave against frames
that have been removed. They do this by adding an iframe element with a
button whose click action removes the iframe element. When the click is
dispatched, the spec would have us generate a mouse event relative to
that iframe, rather than the top-level frame, thus the click would miss
the target button.
Serendipitously, a spec issue and PR were just opened to generate mouse
events relative to the top-level frame. This patch implements that PR;
it has some editorial issues to be resolved, but is a clear improvement
for these tests.
When a platform key press or release event is repeated, we now pass
along a `repeat` flag to indicate that auto-repeating is happening. This
flag eventually ends up in `KeyboardEvent.repeat`.
This implements execution of the pointer up, pointer down, and pointer
move actions.
This isn't 100% complete. Pointer move actions are supposed to break
the move into iterations over the specified duration, which we currently
do not do.
