Core
The order of properties used in foreach, var_dump(),
serialize(), object comparison, etc. was changed.
Properties are now ordered naturally according to their declaration
and inheritance. Properties declared in a base class are going
to be before the child properties.
This order is consistent with internal layout of properties in
zend_object structure and repeats the order in
default_properties_table[] and properties_info_table[].
The old order was not documented and was caused by class inheritance implementation details.