Cut down on usage of deprecated APIs in //crypto.

SSL_library_init is deprecated. It's CRYPTO_library_init. Switch from the
legacy ASN.1 APIs to the new parsers where feasible.
ECPrivateKey::CreateFromEncryptedPrivateKeyInfo is left alone for now as we
still need a new version of those APIs.

This also adds a scoper for CBB for use in later CLs.

BUG=499653

Review URL: https://codereview.chromium.org/1739403002

Cr-Commit-Position: refs/heads/master@{#378610}
diff --git a/crypto/BUILD.gn b/crypto/BUILD.gn
index 035e5cb..4e339ccc 100644
--- a/crypto/BUILD.gn
+++ b/crypto/BUILD.gn
@@ -13,6 +13,7 @@
     "apple_keychain.h",
     "apple_keychain_ios.mm",
     "apple_keychain_mac.mm",
+    "auto_cbb.h",
     "capi_util.cc",
     "capi_util.h",
     "crypto_export.h",
@@ -158,6 +159,7 @@
     sources -= [
       "aead_openssl.cc",
       "aead_openssl.h",
+      "auto_cbb.h",
       "curve25519_openssl.cc",
       "ec_private_key_openssl.cc",
       "ec_signature_creator_openssl.cc",