Valgrind: Use BaseTreeView instead of QTreeView

Change-Id: Ica796ba3d45b97fb5ed0856acb0860f15d45be56
Reviewed-by: hjk <hjk121@nokiamail.com>
Valgrind: De-pimpl Valgrind::Internal::CostView

No need for that in internal classes.

Change-Id: Id2e2783972e068cef9873c248ae54c013b933530
Reviewed-by: hjk <hjk121@nokiamail.com>
Debugger: Select usable frame on stop

Change-Id: I37305aa6b44b7b9edf33a6828d965ab84289e353
Reviewed-by: hjk <hjk121@nokiamail.com>