ProjectExplorer: Standardize RunWorker creation logic

This unifies the remaining paths of RunWorker creation to always
use RunWorkerFactories in the plugin pimpls.

There were, and are, still effectively three basic kinds of workers:
 - "toplevel" tools corresponding to the run modes, that are often all
    that's used for local runs and directly started via the fat buttons
    or e.g. entries in the analyze menu, with factories already previously
    located in the plugin pimpls
 -  core "tool helpers", providing tool specific functionality typically
    used in conjunction with a remote device specific run mechanism,
    set up via RunControl::registerWorkerCreator
 -  target/device specific runhelper like port gatherers contructed e.g.
    via *Device::workerCreator(Core::Id id)

Worse, these categories are partially overlapping, so it was not
clear how a "clean" setup would look like, instead some ad-hoc cobbling
"to make it work" happened.

In some cases, the runMode id was used throughout the whole ensemble
of run workers for a given run, and which worker exactly was created
depended on which of the mechanism above was used in which order.

With the new central setup, the top-level runmodes remain, but the
second kind gets new ids, so the implicit dependencies on order
of setup mechanism are avoided.

This also helps in the cases where there was previously unclarity of where
and how to set up worker factories: It's always and only the plugin
pimpl now.

Change-Id: Icd9a08e2d53e19abe8b21fe546f469fae353a69f
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

src/plugins/android/androidrunnerworker.h

@@ -26,7 +26,7 @@
 
 #pragma once
 
-#include <projectexplorer/runconfiguration.h>
+#include <projectexplorer/runcontrol.h>
 
 #include <qmldebug/qmldebugcommandlinearguments.h>