Add the start of the TimelineOverview class.

TimelineOverview currently has a time ruler and tracks the current recording time.

https://bugs.webkit.org/show_bug.cgi?id=125878

Reviewed by Joseph Pecoraro.

* UserInterface/Main.html:
* UserInterface/TimelineContentView.css:
(.content-view.timeline > .timeline-overview):
* UserInterface/TimelineContentView.js:
(WebInspector.TimelineContentView):
(WebInspector.TimelineContentView.prototype.updateLayout):
(WebInspector.TimelineContentView.prototype._update):
(WebInspector.TimelineContentView.prototype._recordingStarted):
(WebInspector.TimelineContentView.prototype._recordingStopped):
(WebInspector.TimelineContentView.prototype._recordingReset):
* UserInterface/TimelineManager.js:
(WebInspector.TimelineManager.prototype.eventRecorded.processRecord):
(WebInspector.TimelineManager.prototype.eventRecorded):
* UserInterface/TimelineMarker.js: Renamed from Source/WebInspectorUI/UserInterface/TimelineEventMarker.js.
(WebInspector.TimelineMarker):
(WebInspector.TimelineMarker.prototype.get time):
(WebInspector.TimelineMarker.prototype.set time):
(WebInspector.TimelineMarker.prototype.get type):
* UserInterface/TimelineOverview.css: Added.
(.timeline-overview > .scroll-container):
(.timeline-overview > .scroll-container > .timeline-ruler):
* UserInterface/TimelineOverview.js: Added.
(WebInspector.TimelineOverview):
(WebInspector.TimelineOverview.prototype.get element):
(WebInspector.TimelineOverview.prototype.get startTime):
(WebInspector.TimelineOverview.prototype.set startTime):
(WebInspector.TimelineOverview.prototype.get secondsPerPixel):
(WebInspector.TimelineOverview.prototype.set secondsPerPixel):
(WebInspector.TimelineOverview.prototype.get endTime):
(WebInspector.TimelineOverview.prototype.set endTime):
(WebInspector.TimelineOverview.prototype.addMarker):
(WebInspector.TimelineOverview.prototype.revealMarker):
(WebInspector.TimelineOverview.prototype.updateLayout):
(WebInspector.TimelineOverview.prototype._updateElementWidth):
(WebInspector.TimelineOverview.prototype._needsLayout):
* UserInterface/TimelineRecording.js:
(WebInspector.TimelineRecording.prototype.get startTime):
(WebInspector.TimelineRecording.prototype.get endTime):
(WebInspector.TimelineRecording.prototype.reset):
* UserInterface/TimelineRuler.css:
(.timeline-ruler > .markers):
(.timeline-ruler > .markers > .marker):
(.timeline-ruler > .markers > .marker.current-time):
(.timeline-ruler > .markers > .marker.current-time::before):
(.timeline-ruler > .markers > .marker.load-event):
(.timeline-ruler > .markers > .marker.dom-content-event):
(.timeline-ruler > .markers > .marker.timestamp):
* UserInterface/TimelineRuler.js:
(WebInspector.TimelineRuler):
(WebInspector.TimelineRuler.prototype.updateLayout):
(WebInspector.TimelineRuler.prototype._needsLayout):
(WebInspector.TimelineRuler.prototype._needsMarkerLayout.update):
(WebInspector.TimelineRuler.prototype._needsMarkerLayout):
(WebInspector.TimelineRuler.prototype._recalculate):
(WebInspector.TimelineRuler.prototype._updateLeftPositionOfElement):
(WebInspector.TimelineRuler.prototype._updateMarkers):
(WebInspector.TimelineRuler.prototype._timelineMarkerTimeChanged):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@162408 268f45cc-cd09-0410-ab3c-d52691b4dbfc