IMC: Remove old #if'd-out workaround code for Mac
IMC: Remove old #if'd-out workaround code for Mac

Remove old code that is only enabled if OSX_BLEMISH_HEURISTIC == 0.

It was confusing that there are two sets of workaround code in this
file, and that the older workaround was enabled by setting
OSX_BLEMISH_HEURISTIC == 0.

There should be no good reason for keeping old code around via #ifs
like this given that we have version control.

This workaround was non-functional anyway:
 * Before the imc_connect()/imc_accept() change that I made for
   http://code.google.com/p/nativeclient/issues/detail?id=344, socket
   descriptors were never transferred in messages in nacl_imc.cc, so
   this workaround would never kick in.
 * Even after that change, the Mac kernel bug would not break the
   socket FDs that are transferred in nacl_imc.cc to the extent that
   imc_connect()/imc_accept() would not work.

BUG=http://code.google.com/p/nativeclient/issues/detail?id=1834
TEST=trybots (this is dead code removal)

Review URL: http://codereview.chromium.org/7062010

git-svn-id: 721b910a23eff8a86f00c8fd261a7587cddf18f8@5413 fcba33aa-ac0c-11dd-b9e7-8d5594d729c2

nacl-webkit/native_client,sbc100/native_client,nacl-webkit/native_client,sbc100/native_client,sbc100/native_client,nacl-webkit/native_client,nacl-webkit/native_client,nacl-webkit/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client