SIP: escape button doesn't work on dedicated call tab

In chat tabs for dedicated SIP calls, the escape key doesn't work to close the tab. When escape is pressed, the normal window close logic should be activated:

• If on a call, prompt to ask the user if they really want to end the call.

• If the call is already ended, close the window without prompting.

Not having the escape key available makes it a pain to do window management of calls.