Reviewed by Yury Semikhatsky.

        Web Inspector: TextEditor should support editing a range.
        https://bugs.webkit.org/show_bug.cgi?id=59688

        * inspector/front-end/TextViewer.js:
        (WebInspector.TextEditorChunkedPanel.prototype.makeLineAChunk):
        (WebInspector.TextEditorChunkedPanel.prototype._splitChunkOnALine):
        (WebInspector.TextEditorMainPanel.prototype.setEditableRange):
        (WebInspector.TextEditorMainPanel.prototype.clearEditableRange):
        (WebInspector.TextEditorMainPanel.prototype._splitChunkOnALine):
        (WebInspector.TextEditorMainPanel.prototype._applyDomUpdates):
        (WebInspector.TextEditorMainChunk):
        (WebInspector.TextEditorMainChunk.prototype.set expanded):
        (WebInspector.TextEditorMainChunk.prototype.set readOnly):
        (WebInspector.TextEditorMainChunk.prototype.get readOnly):
        (WebInspector.TextEditorMainChunk.prototype._updateElementReadOnlyState):
        * inspector/front-end/textViewer.css:
        (.text-editor-read-only):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@86446 268f45cc-cd09-0410-ab3c-d52691b4dbfc