Merge 116672 - Web Inspector: search title is shown beside the search field (not under) in the vert…

Merge 116672 - Web Inspector: search title is shown beside the search field (not under) in the vertical mode.
https://bugs.webkit.org/show_bug.cgi?id=86120

Reviewed by Yury Semikhatsky.

This change makes search title render as placeholder at all times.
It also adjusts the size of the search field when navigation arrows appear.

* inspector/front-end/SearchController.js:
(WebInspector.SearchController):
(WebInspector.SearchController.prototype.updateSearchLabel):
(WebInspector.SearchController.prototype._updateSearchNavigationButtonState):
(WebInspector.SearchController.prototype._createSearchNavigationButton):
* inspector/front-end/inspector.css:
(#toolbar-search-item):
(.with-navigation-buttons #search):
(.toolbar-search-navigation-label):
(.with-navigation-buttons .toolbar-search-navigation-label):
* inspector/front-end/inspector.html:

TBR=pfeldman@chromium.org
BUG=126550
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=117228