Now the method can be used to get the fully qualified name of
destructors, operator-ids and conversion-function-ids.

Revert "Revert "Try to fix the type rewriter.""

This reverts commit c9bc1e7c.

This reverts commit 33b19f02.

We need to add the fully qualified name to the case statements.

Reviewed-by: Roberto Raggi

Merge-request: 2167
Reviewed-by: Kai Koehne <kai.koehne@nokia.com>

Done-with: Erik Verbruggen

Done-with: Erik Verbruggen

Reviewed-by: Roberto Raggi

I hate this commit, but unfortunately, I don't have time right now
to finish the new template instantion algorithm so I have to
enable the old way of doing instantiations.

Task-number: QTCREATORBUG-1776

Done-with: Erik Verbruggen

Previously, it would still fail if a forward declaration and declaration
for a class were in the same file.

Task-number: QTCREATORBUG-20

columnNumber() relies on text wrapping, and we're only interested in the
position of the cursor in the block.