Reproducible crash
 

Title: Crash when OWOpenNewFramesInTabs is set and you close tabs created from a popup.

Steps:
0. Make sure that the OWOpenNewFramesInTabs setting is set to true.
1. Create a new browser.
2. Hit Cmd-T to create a new tab.
3. Visit [url]www.applesinsider.com[/url] (misspelling intentional)
4. The site above will generate two popups and thus three tabs, 1 for the original site and 2 for the popups.
5. Hit Cmd-W repeatedly to close the new tabs.

Actual: After closing the tab for the applesinsider page, OW sp5 crashes.

Expected: No crash.

Call stack:
0 -- 0x90a4e387 -- _objc_msgSend
1 -- 0x0005b7b4 -- -[OWBrowserController closeTab:activateNext:]
2 -- 0x00059c7a -- -[OWBrowserController closeTab:]
3 -- 0x934681bc -- -[NSApplication sendAction:to:from:]
4 -- 0x93515f0f -- -[NSMenu performActionForItemAtIndex:]
5 -- 0x93515c51 -- -[NSCarbonMenuImpl performActionWithHighlightingForItemAtIndex:]
6 -- 0x935158a8 -- -[NSMenu performKeyEquivalent:]
7 -- 0x935152ca -- -[NSApplication _handleKeyEquivalent:]
8 -- 0x9344928f -- -[NSApplication sendEvent:]
9 -- 0x003cd259 -- -[OAApplication sendEvent:]
10 -- 0x93374466 -- -[NSApplication run]
11 -- 0x003c9773 -- -[OAApplication run]
12 -- 0x93368397 -- _NSApplicationMain
13 -- 0x00028c6c -- _main
14 -- 0x00029ea2 -- __start
15 -- 0x00002af5 -- start

Note: Is it expected behavior that the tabs generated from popups have no toolbar and no status bar?