Still too unstable after all.

This reverts commit 6f3c9f70.

This reverts commit 84ba24ac.

It might work now cause of the fix done in commit
f3767148.

Task: 249227

Crashes, Roberto will fix properly later.

There is no need to "expand" again the scope we get from invoking `resolve'.
(cherry picked from commit c72c84d8)

There is no need to "expand" again the scope we get from invoking `resolve'.

There is no need to "expand" again the scope we get from invoking `resolve'.

Return early in this case.

Reviewed-by: Roberto Raggi

This should simplify the merging of the improved lookup context.

This change removes a number of wrong usages of the CppModelManager::documents()/document().