avoid returning default namespace when searching from an attribute reverse

* tree.c: avoid returning default namespace when searching
  from an attribute
* entities.c xmlwriter.c: reverse xmlEncodeSpecialChars() behaviour
  back to escaping " since the normal serialization routines do not
  use it anymore, should close bug #134477 . Tried to make
  the writer avoid it too but it didn't work.
Daniel
4 files changed