Web Inspector: paint box model colors in Metrics sidebar at all times, do not draw...

Web Inspector: paint box model colors in Metrics sidebar at all times, do not draw box outlines.
https://bugs.webkit.org/show_bug.cgi?id=68240

Today we paint backgrounds in Metrics box model on hover only - should be painted at all
times for the reference. Outlining boxes is highlight is wrong since outlines are outside
the corresponding box regions. We've seen few reports on that + Firebug does not do borders
for that reason.

Reviewed by Yury Semikhatsky.

* inspector/DOMNodeHighlighter.cpp:
* inspector/DOMNodeHighlighter.h:
* inspector/Inspector.json:
* inspector/InspectorDOMAgent.cpp:
(WebCore::InspectorDOMAgent::setHighlightDataFromConfig):
* inspector/front-end/Color.js:
* inspector/front-end/MetricsSidebarPane.js:
(WebInspector.MetricsSidebarPane.prototype._highlightDOMNode):
(WebInspector.MetricsSidebarPane.prototype._updateMetrics):
* inspector/front-end/inspector.css:
(.metrics .label):
* inspector/front-end/inspector.js:
(WebInspector.buildHighlightConfig):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@95621 268f45cc-cd09-0410-ab3c-d52691b4dbfc