Implement TimelineRecording and per-call-site timelines.

Keep track of timeline records per global timeline and per source code location.
This will be used to display them in the UI in later patches.

https://bugs.webkit.org/show_bug.cgi?id=123367

Reviewed by Joseph Pecoraro.

* UserInterface/Main.html:
* UserInterface/SourceCodeTimeline.js: Added.
(WebInspector.SourceCodeTimeline):
(WebInspector.SourceCodeTimeline.prototype.get sourceCode):
(WebInspector.SourceCodeTimeline.prototype.get sourceCodeLocation):
(WebInspector.SourceCodeTimeline.prototype.get recordType):
(WebInspector.SourceCodeTimeline.prototype.get recordEventType):
* UserInterface/Timeline.js: Added.
(WebInspector.Timeline):
(WebInspector.Timeline.prototype.get records):
(WebInspector.Timeline.prototype.addRecord):
* UserInterface/TimelineRecording.js:
(WebInspector.TimelineRecording):
(WebInspector.TimelineRecording.prototype.get timelines): Added.
(WebInspector.TimelineRecording.prototype.sourceCodeTimelinesForSourceCode): Added.
(WebInspector.TimelineRecording.prototype.addEventMarker): Implemented.
(WebInspector.TimelineRecording.prototype.addRecord): Implemented.
(WebInspector.TimelineRecording.prototype._keyForRecord): Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@162401 268f45cc-cd09-0410-ab3c-d52691b4dbfc