As of Qt 4.8 the observer and jsdebugger services are part of Qt. This
means the following changes are necessary in Qt Creator:
* Do not link to the QmlJSDebugger library.
* Do not create JSDebuggerAgent and QDeclarativeViewObserver instances
in the QmlApplicationViewer and use the new declarative_debug CONFIG
option to enable those services in Qt. This is done automatically
for debug builds.
* Point out the QML Debugging Library and the QML Observer are "Not
needed" in the Qt options page.
* Change the label in qmake options from "Link QML debugging library" to
"Enable QML debugging". It still remains as a way to enable this
functionality in release builds or for QtQuick applications not based
on Qt Creator's template.
* Rely on qmlviewer for debugging QML UI projects rather than the
observer, which is no longer necessary.
Reviewed-by: Kai Koehne
This makes sure it gets deleted together with the QmlApplicationViewer,
rather than probably not at all when no parent is specified for the
viewer (which is the default).
Reviewed-by: Alessandro Portale
Reviewed-by: Christiaan Janssen
