Automatic management of OpenSSL error stack
Automatic management of OpenSSL error stack

This removes some complexity in remembering to free the OpenSSL error
stack. If you forget, the error will stick around until you make another
call.

Change-Id: I245a525dcc93077b2bf9909a14a0ef469a2daca4

google/conscrypt,google/conscrypt,google/conscrypt,google/conscrypt,google/conscrypt,google/conscrypt