Debugger: Fix map dumper with LLDB-320.x

The underlying problem here is still that we can deduce
the item type from the map type except by string manipulation
and type lookup. Which fails at times.

Change-Id: Ibe6a8ca1fbd84c43c7d31b65e017792d1b6a1e0b
Reviewed-by: Christian Stenger <christian.stenger@theqtcompany.com>
Squish: Let test continue instead of crashing on protocol error

Change-Id: I3c862d26fbbdf124c0b347225cfd97e0748a0830
Reviewed-by: Robert Loehning <robert.loehning@theqtcompany.com>