[Python] Add methods reference_value and const_value to gdb.Value

[Siva Chandra]

Ping.

On Mon, Apr 27, 2015 at 6:30 AM, Siva Chandra <sivachandra@google.com> wrote:
> This will help address libstdc++/65840:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65840
>
> gdb/ChangeLog:
>
> 2015-04-27  Siva Chandra Reddy  <sivachandra@google.com>
>
>         * NEWS (Python Scripting): Mention the new gdb.Value methods.
>         * python/py-value.c (valpy_reference_value): New function.
>         (valpy_const_value): Likewise.
>         (value_object_methods): Add new methods.
>         * value.c (make_cv_value): New function.
>         * value.h (make_cv_value): Declare.
>
> gdb/doc/ChangeLog:
>
> 2015-04-27  Siva Chandra Reddy  <sivachandra@google.com>
>
>         * python.texi (Values From Inferior): Add descriptions of new
>         methods gdb.Value.reference_value and gdb.Value.const_value.
>
> gdb/testsuite/ChangeLog:
>
> 2015-04-27  Siva Chandra Reddy  <sivachandra@google.com>
>
>         * gdb.python/py-xmethods.cc: Enhance test case.
>         * gdb.python/py-xmethods.exp: New tests.
>         * gdb.python/py-xmethods.py (A_indexoper): New xmethod worker
>         function.
>         (B_indexoper): Likewise.
>         (global_dm_list) : Add new xmethod worker functions.