Description:
------------
PHP does not emit a warning of any kind when defining a function with a required 
parameter after an optional parameter. For example:
function foo($optional = 1, $required) {}

It doesn't make sense to define a required parameter after an optional one, 
since 
that effectively makes all preceding optional parameters required. Since this is 
an error that can produce bugs and other warnings if one is not careful (calling 
the above function with less than two parameters will cause warnings to be 
emitted 
for the missing $required parameter), PHP should emit a warning of some kind 
when 
functions like this are defined.

The attached patch includes the following changes:

* add an E_STRICT warning when such a function is defined. (The warning will 
only 
appear when E_STRICT is included in the php.ini, since it happens at script 
compile time, before error_reporting can be called.)

* add Zend/tests/func_optarg1.phpt and Zend/tests/func_optarg2.phpt to test for 
the presence and absence of the warning

* Fixes Zend/tests/call_user_func_005.phpt, which fails with the warning added.