Fixes #11088: IDLE crashes when using F5 to run a script on OSX with Tk 8.5

Without this patch IDLE will crash reliably on OSX when Tkinter
is linked to TkCocoa 8.5.x.

To reproduce:

* Create a new file (script.py) with the following two lines:

x = input('prompt: ')
print(x)

* Save the script

* Run the script using the F5 keyboard shortcut
  (running from the menu works fine)

The patch is a fairly crude hack, but we haven't found a better
workaround for this Tk bug yet.

diff --cc Misc/NEWS
index c214cc588984c5034c4a98896ffd8d09c90cb040,c40136cca60c6ba2216d1bd3c64877d813bbefaf..b6900091fb40ea5ecfe84cfe5228e04ffcfc5710
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -153,66 -164,8 +153,69 @@@ Core and Builtin
  Library
  -------
  
 -- Issue #11927: SMTP_SSL now uses port 465 by default as documented.  Patch by
 -  Kasun Herath.
++- Issue #11088: don't crash when using F5 to run a script in IDLE on MacOSX
++  with Tk 8.5.
++
 +- Issue #9516: Issue #9516: avoid errors in sysconfig when MACOSX_DEPLOYMENT_TARGET
 +  is set in shell.
 +
 +- Issue #8650: Make zlib module 64-bit clean. compress(), decompress() and
 +  their incremental counterparts now raise OverflowError if given an input
 +  larger than 4GB, instead of silently truncating the input and returning
 +  an incorrect result.
 +
 +- Issue #12050: zlib.decompressobj().decompress() now clears the unconsumed_tail
 +  attribute when called without a max_length argument.
 +
 +- Issue #12062: Fix a flushing bug when doing a certain type of I/O sequence
 +  on a file opened in read+write mode (namely: reading, seeking a bit forward,
 +  writing, then seeking before the previous write but still within buffered
 +  data, and writing again).
 +
 +- Issue #9971: Write an optimized implementation of BufferedReader.readinto().
 +  Patch by John O'Connor.
 +
 +- Issue #1028: Tk returns invalid Unicode null in %A: UnicodeDecodeError.
 +  With Tk < 8.5 _tkinter.c:PythonCmd() raised UnicodeDecodeError, caused
 +  IDLE to exit.  Converted to valid Unicode null in PythonCmd().
 +
 +- Issue #11799: urllib.request Authentication Handlers will raise a ValueError
 +  when presented with an unsupported Authentication Scheme. Patch contributed
 +  by Yuval Greenfield.
 +
 +- Issue #10419, #6011: build_scripts command of distutils handles correctly
 +  non-ASCII path (path to the Python executable). Open and write the script in
 +  binary mode, but ensure that the shebang is decodable from UTF-8 and from the
 +  encoding of the script.
 +
 +- Issue #8498: In socket.accept(), allow to specify 0 as a backlog value in
 +  order to accept exactly one connection.  Patch by Daniel Evers.
 +
 +- Issue #12011: signal.signal() and signal.siginterrupt() raise an OSError,
 +  instead of a RuntimeError: OSError has an errno attribute.
 +
 +- Issue #3709: a flush_headers method to BaseHTTPRequestHandler which manages
 +  the sending of headers to output stream and flushing the internal headers
 +  buffer. Patch contribution by Andrew Schaaf
 +
 +- Issue #11743: Rewrite multiprocessing connection classes in pure Python.
 +
 +- Issue #11164: Stop trying to use _xmlplus in the xml module.
 +
 +- Issue #11888: Add log2 function to math module. Patch written by Mark
 +  Dickinson.
 +
 +- Issue #12012: ssl.PROTOCOL_SSLv2 becomes optional.
 +
 +- Issue #8407: The signal handler writes the signal number as a single byte
 +  instead of a nul byte into the wakeup file descriptor. So it is possible to
 +  wait more than one signal and know which signals were raised.
 +
 +- Issue #8407: Add pthread_kill(), sigpending() and sigwait() functions to the
 +  signal module.
 +
 +- Issue #11927: SMTP_SSL now uses port 465 by default as documented.  Patch
 +  by Kasun Herath.
  
  - Issue #12002: ftplib's abort() method raises TypeError.