When parsing a numeric literal in a line like "a=0x0e+b|0;",
currently the scanner consumes the "e+" part (as it thinks
it's the start of an exponent).
In the ECMAScript lexical grammar HexIntegerLiteral cannot
contain exponents, which means the '+' character should be
parsed as a binary operator.

R=bradnelson@chromium.org
BUG=v8:7893

Change-Id: I97a0d4ea2ee1d38a3462efbfaef5eb87b8ea704b
Reviewed-on: https://chromium-review.googlesource.com/1116551Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54132}