e.g., when the engine is not ready

these missed the handleExecContinue() callback, so they got missed last
time. added both callback and flag, and some more glue to the gross
isBogus hack.

as it turns out, it is not possible to set pending breakpoints until
gdb has loaded as image. so add some hooks to enable adapters to trigger
the initial breakpoint syncing at the right time. do not add additional
states (say, InferiorPreparing), as it would just complicate things.

this includes:
- move the gdb ownership back to the engine (thus strip down the
  adaptors as far as possible)
- make gdb startup synchronous
- make adapter shutdown synchronous
- fix the state transitions relating to shutdown

Reviewed by: Friedemann Kleint

This should save debugger round trips and crashes in the debugging
helpers.
Add respective option to debugging helper option page, defaulting to
true.On this occasion, make CDB detect shadowed variables correctly
and display them as "<shadowed n>" as does the Gdb engine by
reversing the direction in which
CdbSymbolGroupContext::populateINameIndexMap works.
Rubber-stamped-by: hjk <qtc-committer@nokia.com>

specifically, this will skip the initial stop at _start when using the
terminal and remote adapters.

after refactoring the trk adapter startup, the split was not necessary
any more. in fact, it seemed fairly arbitrary at this point.

it is currently unused. do not just remove it, as hjk says he wants to
revive it.

each command can have only one of two legitimate responses: "error" or -
depending on the command, and thus declared via a flag - "done" or
"running".
this is way nicer than sprinkling the code with else-ifs (where elses
are sufficient) and asserts all over the place - and silently failing in
release builds.

For the case that gdb can give all the interesting data in one go.

this drastically improves the usefulness of the debugger output window
by making internal and external messages appear in sync.

fixes build

don't evaluate expression for possible reset if the variable is already
unset ...

Add a configuration checking method to the Debugger manager,
depending on toolchain, wire it to the engines.
Check that in the debugger run controls.

Add a convenience method to ICore that shows a warning
message with a "Settings" button, pointing the user
to a configuration error on a settings page.

Remove leftovers of the dumper parser.
Acked-by: con <qtc-committer@nokia.com>

at least in theory, this is the output of a remote debuggee