Prevent a crash when the item is deleted but not removed from cache

If the item is not removed from the cache when it is deleted then the
cache can end up pointing to an invalid item which when accessed will
cause a crash.

Task-number: QTBUG-38430

[ChangeLog][QtQml] Prevent a crash when the item is deleted
but is not removed from the QQmlDelegateModel's cache.

Change-Id: I8cf76b014be62a432d909a3573231cec84a6d678
Reviewed-by: Alan Alpert <aalpert@blackberry.com>
Make sure the clipPath is retained as state of Context2D

The W3C spec doesn't say anything about the clip path getting reset
automatically at any point and so I guess we should retain it. This of
course is terribly annoying if the canvas element gets resized and ends
up with a default clipPath that doesn't match the canvas anymore. You
basically have to call reset() in every onPaint now. However, this just
highlights a general problem with stateful canvas contexts and we cannot
ignore user defined clipPaths like this.

Task-number: QTBUG-38297
Change-Id: I233226af6458298ef3d752d08ecdebebae2e0a8f
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
QQuickItemView/QQuickPathView: Fix creation of delegates

When the delegate is set before the model and
after the ItemView/PathView has been created

Task-number: QTBUG-38368
Change-Id: I6963abe28087699cf4e8921153dc7641bae3b220
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>
qmlplugindump: correctly merge composite types

When hiding part of the hierarchy during the merging of composite
types properties/methods/signals that are hidden should not be dumped
twice.

Task-number: QTBUG-38354
Change-Id: I328cf25dd5a70e1c0fce017e8ae572e8a9e56245
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
Reviewed-by: Alan Alpert <aalpert@blackberry.com>