Bug 1818: Do not relly on xml.isNameSpaceRepairing

Last code path which indirectly relied on name space
repairing was write out of writeStartElement.

This was converted to look into parent namespace
and writeStartElement and writeDefaultNamespace
when namespace change.

Change-Id: I511436e9eab98e0c35eb100dfe0627cd5edd53b6
Signed-off-by: Tony Tkacik <ttkacik@cisco.com>