[new compiler] Add the correct object index to the custom parser

Without the correct index the calls to astForBinding run out of bounds. Fixes
tst_qqmllistmodel crash.

Change-Id: I6fb8b77866cbf247e7373cdbece6833c92be3615
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
[new compiler] Fix warnings in qml list model custom parser

For the warnings to have the correct column/line number information, we
need to set it on the QQmlData before calling the custom parser.

Change-Id: I6e1c729491df6af846e41ee88e785b32e4715751
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Fix calls to overloaded slots for QObjects not created by QML

If we don't have a property cache, we need to fall back to a slower method of
determining the overload methods. We have the code for that in RelatedMethod,
once we determine that we're calling overloads, but we never hit that code path
because we did not _initially_ determine that the method was an overload.

Task-number: QTBUG-37157
Change-Id: I8ff39156e5668236b3797400b4086ed545624398
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Make it possible to call QQmlEngine::setObjectOwnership at any time

QJSEngine::newQObject should call setObjectOwnership only if it wasn't
called before, to preserve any policy set by the user earlier. Otherwise
it's only safe to call after newQObject and then you'd have to call it
_every_ time the QObject is wrapped, at all call sites. Instead this
patch preserves any policy set.

Task-number: QTBUG-37160

Change-Id: I6178fa38cd7f4b09d818b6f18762c21588562422
Reviewed-by: Lars Knoll <lars.knoll@digia.com>