[new compiler] Fix propagation of imported scripts for anonymous components

We must take the imported scripts from the creation context. Fixes various
errors in Qt Quick Controls.

Change-Id: I336d8ffa0537cefd4eeac15f98bbf1b0a5c784af
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
[new compiler] Fix crash in qml delegate model

qmlContext(this) is expected in re-implementations of classBegin(), so just
like the VME we have to be careful that we call it after setting the context
on the ddata.

Change-Id: I38ad8d1a4e4093368f62f9d57718de3b8cd0cfd2
Reviewed-by: Lars Knoll <lars.knoll@digia.com>