Add crypto/wincrypt_shim.h wrapper header to resolve BoringSSL conflicts.

wincrypt.h defines macros that conflict with BoringSSL. Introduce a
crypto/wincrypt_shim.h wrapper header which #undefs those macros and
instead #defines replacement ones. All Chromium headers should
use this wrapper header.

BUG=338884

Review URL: https://codereview.chromium.org/686883002

Cr-Commit-Position: refs/heads/master@{#301994}
21 files changed