Add missing enumeration value to wheelEventPhaseToString().
Document::scriptRunner() should return a reference.
Inspector: Remove old initialization code for RecordingsObserver.
Fix the build for !ENABLE(TIMELAPSE).

Closes #424.
Rename the TimerFired and TimerCreated inputs to DOMTimerFired and DOMTimerCreated.
Add a replayable timer implementation whose instances are tracked by ReplayProxy.

Closes #411.
Reimplement deterministic async script running with AsyncTimer mechanism.
Reimplement capture/replay of fake mouse move using ReplayTimer.
Reimplement EventSender to use ReplayableTimer.