cehteh on #git noticed that secondary windows such as console windows from push/fetch/merge or the blame browser failed on ion when we tried to open them a second time.
The issue turned out to be the fact that on ion [winfo ismapped .] returns false if . is not visible right now because it has been obscured by another window in the same panel. So we need to keep track of whether or not the root window has been displayed for this application, and once it has been we cannot ever assume that ismapped is going to return true.
Signed-off-by: Shawn O. Pearce <email@example.com>