[css2.1] tokenizer syntax - handling escaped null in badstring

The current tokenizer syntax [1] specifies:

escape  {unicode}|\\[^\r\n\f0-9a-f]
badstring1      \"([^\n\r\f\\"]|\\{nl}|{escape})*\\?

Given the following input string:

< U+0022 (QUOTATION MARK), U+005C (REVERSE SOLIDUS), U+0000 (NULL) >

Does the < U+005C, U+0000 > match escape or does it match the final \\? ?
That is, should U+0000 be treated as an escapable character or as EOF
(EOS)? The above grammar suggests the former.

[1] http://www.w3.org/TR/CSS2/grammar.html