Description:
------------
These OCI8 tests are crashing after the implementation of "interned
string" in the PHP trunk code:

bind_char_1.phpt
bind_char_2.phpt
bind_char_3.phpt
bind_char_4.phpt
bind_rowid.phpt
error_bind.phpt

This is due to a realloc in php_oci_bind_post_exec() to add a null
terminator for bound data.  The crash happens on IN binds that are
interned since realloc is not permitted for interned strings.  Because
string IN binds are always null terminated the realloc is unnecessary.
Null strings are apparently not interned so modification of their zval
to force an empty string is OK.

String OUT binds have new memory allocated in php_oci_bind_callback()
and are not interned so they can be realloced.  Also all current test
cases already get null terminated output from Oracle.