New perf dashboard should compare results to baseline and target

New perf dashboard should compare results to baseline and target
https://bugs.webkit.org/show_bug.cgi?id=141286

Reviewed by Chris Dumez.

Compare the selected value against baseline and target values as done in v1. e.g. "5% below target"
Also use d3.format to format the selected value to show four significant figures.

* public/v2/app.js:
(App.Pane.searchCommit):
(App.Pane._fetch): Create time series here via createChartData so that _computeStatus can use them
to compute the status text without having to recreate them.
(App.createChartData): Added.
(App.PaneController._updateDetails): Use 3d.format on current and old values.
(App.PaneController._computeStatus): Added. Computes the status text.
(App.PaneController._relativeDifferentToLaterPointInTimeSeries): Added.
(App.AnalysisTaskController._fetchedManifest): Use createChartData as done in App.Pane._fetch. Also
format the values using chartData.formatter.

* public/v2/chart-pane.css: Enlarge the status text. Show the status text in red if it's worse than
the baseline and in blue if it's better than the target.

* public/v2/data.js:
(TimeSeries.prototype.findPointAfterTime): Added.

* public/v2/index.html: Added a new tbody for the status text and the selected value. Also fixed
the bug that we were not showing the old value's unit.

* public/v2/interactive-chart.js:
(App.InteractiveChartComponent._constructGraphIfPossible): Use chartData.formatter. Also cleaned up
the code to show the baseline and the target lines.

* public/v2/manifest.js:
(App.Manifest.fetchRunsWithPlatformAndMetric): Added smallerIsBetter.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@179710 268f45cc-cd09-0410-ab3c-d52691b4dbfc