DevTools: ReplaceAll did not work properly with special chars.

Replace-all of some text with "$&" would be a no-op in text editor.

The "$" is a special character in the second argument of String.prototype.replace(),
thus it should be escaped or a function callback should be used instead.

BUG=
TEST=LayoutTests/inspector/editor/text-editor-search-replace.html
R=vsevik@chromium.org, lushnikov@chromium.org

Review URL: https://chromiumcodereview.appspot.com/22679002

git-svn-id: svn://svn.chromium.org/blink/trunk@155935 bbb929c8-8fbe-4397-9dbb-9b2b20218538