Useful for parsing things when you don't know what tag to expect (e.g. a
CHOICE). Also allow its operands to be NULL, so that it can be used to skip
arbitrary elements.

Delete CBS_ASN1_ANY which wasn't doing anything.

Change-Id: I56413e68b4f2e13860ea3e55373d5830713d7e5c
Reviewed-on: https://boringssl-review.googlesource.com/1661
Reviewed-by: Adam Langley <agl@google.com>

We don't really want to expose this but the bytestring test calls this
function directly and, when linked against a shared library, thus needs
it to be in the dynamic symbol table.

Change-Id: Ife01da36fe142026a6a3e545cff746512b966ee6

Previously, the ASN.1 functions in bytestring were capable of processing
indefinite length elements when the _ber functions were used. That works
well enough for PKCS#3, but NSS goes a bit crazy with BER encoding and
PKCS#12. Rather than complicate the core bytestring functions further,
the BER support is removed from them and moved to a separate function
that converts from BER to DER (if needed).

Change-Id: I2212b28e99bab9fab8c61f80d2012d3e5a3cc2f0
Reviewed-on: https://boringssl-review.googlesource.com/1591
Reviewed-by: Adam Langley <agl@google.com>