Fixes issue26307: The profile-opt build now applys PGO to the built-in modules.

diff --cc Makefile.pre.in
Simple merge

diff --cc Misc/NEWS
index 0438f076f76c627e981944c01a580a2de8f78322,7c62a15bd834c63edf62ea1eed6dccf36f1b6374..b2a86807b3eac3a4872bc91b0a65b382751b75a5
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -10,37 -10,8 +10,39 @@@ What's New in Python 3.6.0 beta 
  Core and Builtins
  -----------------
  
+ - Issue #26307: The profile-opt build now applys PGO to the built-in modules.
+ 
 +- Issue #27078: Added BUILD_STRING opcode.  Optimized f-strings evaluation.
 +
 +- Issue #17884: Python now requires systems with inttypes.h and stdint.h
 +
 +- Issue #27961: Require platforms to support ``long long``. Python hasn't
 +  compiled without ``long long`` for years, so this is basically a formality.
 +
 +- Issue #27355: Removed support for Windows CE.  It was never finished,
 +  and Windows CE is no longer a relevant platform for Python.
 +
 +- Issue #27921: Disallow backslashes in f-strings. This is a temporary
 +  restriction: in beta 2, backslashes will only be disallowed inside
 +  the braces (where the expressions are). This is a breaking change
 +  from the 3.6 alpha releases.
 +
 +- Implement the frame evaluation part of PEP 523.
 +
 +- Issue #27870: A left shift of zero by a large integer no longer attempts
 +  to allocate large amounts of memory.
 +
 +- Issue #25402: In int-to-decimal-string conversion, improve the estimate
 +  of the intermediate memory required, and remove an unnecessarily strict
 +  overflow check. Patch by Serhiy Storchaka.
 +
 +- Issue #27214: In long_invert, be more careful about modifying object
 +  returned by long_add, and remove an unnecessary check for small longs.
 +  Thanks Oren Milman for analysis and patch.
 +
 +- Issue #27506: Support passing the bytes/bytearray.translate() "delete"
 +  argument by keyword.
 +
  - Issue #27812: Properly clear out a generator's frame's backreference to the
    generator to prevent crashes in frame.clear().