[new compiler] Fix timing of property assignment error handling

Most property assignment errors are now handled at type compile time, just
like in the old compiler. This speeds up the object creation code and
restores behavior expected in the qqmllanguage tests.

Change-Id: If213cd0bfa4dd51d9065c27809a79a6495c9f3ce
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
[new compiler] Avoid uncreatable type errors for types that aren't created

QtQuick.Keys for example is not creatable, but it's also never created but
only used as attached properties. Therefore types used as attached properties
create the needCreation = false flag in the referenced types.

Change-Id: I6ca3a3ff677858bf3c55d3e08a0f0fc8ee9160fe
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Add test for shaping and rendering Sinhala text

This is currently broken on Mac OS X, but the fix is nigh.

Task-number: QTBUG-36056
Change-Id: I547f7961a2ca8c62301e15de486a6f75de26bc4a
Reviewed-by: aavit <eirik.aavitsland@digia.com>