Web Inspector: REGRESSION (r213000): copy from Search results content view broken

Web Inspector: REGRESSION (r213000): copy from Search results content view broken
https://bugs.webkit.org/show_bug.cgi?id=187020
<rdar://problem/40928766>

Reviewed by Timothy Hatcher.

Since WI._copy listens for a copy event from the document, it is called
after CodeMirror handles the event and sets clipboard data. If WI._copy
finds a custom copy handler to call, that handler can determine whether
to overwrite the current clipboard data, or leave it alone.

SearchTabContentView's handleCopyEvent method should return early if the
content tree outline doesn't have the focus. This prevents the selection
in the TextEditor from being overwritten, without any special knowledge of
the content browser's current view.

* UserInterface/Views/SearchTabContentView.js:
(WI.SearchTabContentView.prototype.handleCopyEvent):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@233334 268f45cc-cd09-0410-ab3c-d52691b4dbfc