Web Inspector: [Regression] breakpoint condition not editable

Web Inspector: [Regression] breakpoint condition not editable
https://bugs.webkit.org/show_bug.cgi?id=109183

Patch by Andrey Lushnikov <lushnikov@chromium.org> on 2013-02-07
Reviewed by Vsevolod Vlasov.

Improve TextEditorMainPanel.selection() method to return null if the
selection is set inside of decoration element.

No new tests.

* inspector/front-end/DOMExtension.js:
(Node.prototype.enclosingNodeOrSelfWithClass): Improve to add iteration boundary.
* inspector/front-end/DefaultTextEditor.js:
(WebInspector.TextEditorMainPanel.prototype.selection):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@142138 268f45cc-cd09-0410-ab3c-d52691b4dbfc