WebPositive: Previous/next navigation issues

[bonefish]

1. Open new window.
2. Enter ​http://docs.oracle.com/javase/7/docs/api/.
3. Click any link, e.g. "java.applet" in the main sub-page. The toolbar "previous" button doesn't become enabled.
4. Clean another link, e.g. "AppletContext" in the main sub-page. The toolbar "previous" button doesn't become enabled.
5. Open a new tab.
6. Switch back to the first tab. The toolbar "previous" button is enabled now.
7. Click "previous" button. The previous page is show. The "next" button doesn't become enabled.
8. Click "previous" button. No effect.

[pulkomandy]

Duplicate of #10294.