LLDB: avoid python backtraces destroying all data

Change-Id: I1ea7ccad208c00d11e0579de219739cbabab8455
Reviewed-by: hjk <hjk121@nokiamail.com>
LLDB: Fix opening memory view after the first use

We always need to update the editor token even if we already know about
the memory agent, because the editor behind it can change.

Change-Id: I6101b5a5c1ee0698ae7c7668d0766056a19eadb8
Reviewed-by: hjk <hjk121@nokiamail.com>