Fix test always passing in python/py-linetable.exp

The following test is found in python/py-linetable.exp:

gdb_test "python print sorted(fset)" \
    "\[20L, 21L, 22L, 24L, 25L, 28L, 29L, 30L, 32L, 33L, 37L, 39L, 40L, 42L, 44L, 45L, 46L\].*" \
    "Test frozen set contains line numbers"

I noticed that it passed when using Python 3, even though it should fail
because of the missing parentheses for the call print.

There needs to be more escaping of the square brackets. Currently, it is
interpreted as "any one character from this big list of characters,
followed by .*". When adding the required amount of backslashes, the
test starts failing as it should.

Moreover, both in Python 2.7 and Python 3.3 the numbers don't have the L
suffix, so now the test fails because of that. Anybody knows why they
were there in the first place? I just tested with Python 2.4 and there
are no Ls.

gdb/testsuite/ChangeLog:

	* gdb.python/py-linetable.exp: Escape properly sorted(fset)
	test expected output.  Add parentheses for the call to print.
	Remove L suffix from integers.

Signed-off-by: Simon Marchi <simon.marchi@ericsson.com>
python extended prompt: Use os.getcwd() instead of os.getcwdu()

It seems like using os.getcwdu() here is wrong both for Python 2 and Python 3.

For Python 2, this returns a 'unicode' object, which tries to get concatenated
to a 'str' object in substitute_prompt. The implicit conversion works when the
unicode string contains no accent. When it does contain an accent though,
displaying the prompt results in the following error:

(gdb) set extended-prompt \w
...
  File "/home/simark/build/binutils-gdb-python2/gdb/data-directory/python/gdb/prompt.py", line 138, in substitute_prompt
    result += str(cmd(arg))
UnicodeEncodeError: 'ascii' codec can't encode character u'\xe9' in position 49: ordinal not in range(128)

When using os.getcwd() instead, it works correctly. I suppose that Python does
the necessary decoding internally.

For Python 3, this method simply does not exist. It works fine with os.getcwd().

gdb/ChangeLog:

	* python/lib/gdb/prompt.py (_prompt_pwd): Use os.getcwd() instead of
	os.getcwdu().
Fix Python help() test for Python 3

The message displayed when using help() changed a bit with time, so this
adjusts the test accordingly.

gdb/testsuite/ChangeLog:

	* gdb.python/python.exp: Change expected reply to help().
Fix prints in tests for Python 3

Python 3's print requires to use parentheses, so this patch adds them where
they were missing.

gdb/testsuite/ChangeLog:

	* gdb.python/py-linetable.exp: Add parentheses to calls to print.
	* gdb.python/py-type.exp: Same.
	* gdb.python/py-value-cc.exp: Same.
	* gdb.python/py-value.exp: Same.
Fix build with Python 3.4 (PR python/16784)

The type of the function pointer PyOS_ReadlineFunctionPointer (part of the
Python C API), which we use, slightly changed starting with Python 3.4. The
signature when from

PyAPI_DATA(char) *(*PyOS_ReadlineFunctionPointer)(FILE *, FILE *, char *);

to

PyAPI_DATA(char) *(*PyOS_ReadlineFunctionPointer)(FILE *, FILE *, const char *);

The parameter that changed is the prompt text.

This commits adjust gdb accordingly by making the prompt_arg parameter const,
as well as the fallouts of that. I needed to rework how annotations are added
to the prompt, since the it is now const. If annotations are enabled, it will
make a copy of the prompt and then overwrite prompt_arg to point to the
annotated prompt. Otherwise, no copy is done and the original prompt_arg is
passed.

I changed the signature of deprecated_readline_hook. I would've changed any
user of it, but it seems like nothing is using it,

Built-tested with python 2.7.x, 3.3.y and 3.4.z.

Signed-off-by: Simon Marchi <simon.marchi@ericsson.com>
Add more missing parentheses to Python calls to print

I noticed that there are calls to Python's print outside the gdb.python
directory, so this patch adds those that I found were missing.  They were
found by grepping for "python print [^(]", so it's always possible that
I missed some others that use another pattern.

gdb/testsuite/ChangeLog:

	* gdb.ada/py_range.exp: Add missing parentheses.
	* gdb.dwarf2/symtab-producer.exp: Same.
	* gdb.gdb/python-interrupts.exp: Same.
	* gdb.gdb/python-selftest.exp: Same.