Checks have been simplified and optimized for most-used cases.

Calling Buffer with another Buffer as the subject will now use the
SlowBuffer Copy method instead of the for loop.

No need to call for value coercion, just place the ternary inline.

It's not used outside of src/node.cc so make it static.

ASN1_STRING_to_UTF8() passes an ASN1_STRING to ASN1_STRING_set() but forgot to
initialize the `length` field.

Fixes the following valgrind error:

  $ valgrind -q --track-origins=yes --num-callers=19 \
      out/Debug/node test/simple/test-tls-client-abort.js
  ==2690== Conditional jump or move depends on uninitialised value(s)
  ==2690==    at 0x784B69: ASN1_STRING_set (asn1_lib.c:382)
  ==2690==    by 0x809564: ASN1_mbstring_ncopy (a_mbstr.c:204)
  ==2690==    by 0x8090F0: ASN1_mbstring_copy (a_mbstr.c:86)
  ==2690==    by 0x782F1F: ASN1_STRING_to_UTF8 (a_strex.c:570)
  ==2690==    by 0x78F090: asn1_string_canon (x_name.c:409)
  ==2690==    by 0x78EF17: x509_name_canon (x_name.c:354)
  ==2690==    by 0x78EA7D: x509_name_ex_d2i (x_name.c:210)
  ==2690==    by 0x788058: ASN1_item_ex_d2i (tasn_dec.c:239)
  ==2690==    by 0x7890D4: asn1_template_noexp_d2i (tasn_dec.c:746)
  ==2690==    by 0x788CB6: asn1_template_ex_d2i (tasn_dec.c:607)
  ==2690==    by 0x78877A: ASN1_item_ex_d2i (tasn_dec.c:448)
  ==2690==    by 0x7890D4: asn1_template_noexp_d2i (tasn_dec.c:746)
  ==2690==    by 0x788CB6: asn1_template_ex_d2i (tasn_dec.c:607)
  ==2690==    by 0x78877A: ASN1_item_ex_d2i (tasn_dec.c:448)
  ==2690==    by 0x787C93: ASN1_item_d2i (tasn_dec.c:136)
  ==2690==    by 0x78F5E4: d2i_X509 (x_x509.c:141)
  ==2690==    by 0x7C9B91: PEM_ASN1_read_bio (pem_oth.c:81)
  ==2690==    by 0x7CA506: PEM_read_bio_X509 (pem_x509.c:67)
  ==2690==    by 0x703C9A: node::crypto::SecureContext::AddRootCerts(v8::Arguments const&) (node_crypto.cc:497)
  ==2690==  Uninitialised value was created by a stack allocation
  ==2690==    at 0x782E89: ASN1_STRING_to_UTF8 (a_strex.c:560)

When perlasm generates MASM code it sets the assembler target to 468.
In this mode MASM refuses to assemble a couple of instructions. Bumping
the target to 686 solves this problem.

It used to be off before. It's extremely unlikely that such an attack
would be a viable attack against node. And it makes AES much slower.

For throughput benchmarks, run with just 5s durations rather than 1s and 3s.

For startup benchmark, run with just a single 1s duration, since it's very
consistent anyway.

Remove ab, since it's no longer used.

Also, make it work properly with current node.

Better covered by the other benchmark/fs scripts.

x