Web Inspector: Fix minor design issues in the Spectrum color picker

Web Inspector: Fix minor design issues in the Spectrum color picker
https://bugs.webkit.org/show_bug.cgi?id=78693

Drive-by: frontend compilability fixes.
Reviewed by Pavel Feldman.

* English.lproj/localizedStrings.js:
* inspector/compile-front-end.sh:
* inspector/front-end/ElementsPanel.js:
* inspector/front-end/Popover.js:
* inspector/front-end/Spectrum.js:
(WebInspector.Spectrum.rgbaToHSVA):
(WebInspector.Spectrum.prototype.set color):
(WebInspector.Spectrum.prototype.get isVisible):
(WebInspector.Spectrum.prototype.toggle):
(WebInspector.Spectrum.prototype.show):
(WebInspector.Spectrum.prototype.hide):
* inspector/front-end/StylesSidebarPane.js:
(WebInspector.StylePropertyTreeElement.prototype.updateTitle.):
* inspector/front-end/elementsPanel.css:
(.spectrum-container):
(.spectrum-top):
(.spectrum-color):
(.spectrum-hue):
(.spectrum-fill):
(.spectrum-range-container):
(.spectrum-range-container *):
(.spectrum-range-container label):
(.spectrum-range-container input):
(.swatch, .spectrum-dragger, .spectrum-slider):
(.spectrum-sat):
(.spectrum-val):
(.spectrum-dragger):
(.spectrum-slider):
* inspector/front-end/inspector.css:
(.custom-popup-vertical-scroll ::-webkit-scrollbar-track-piece:vertical:increment):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@107810 268f45cc-cd09-0410-ab3c-d52691b4dbfc