LGTM.

The Chromium bug report is not accessible?

Basically it has been causing crash reports on chrome canary. Access is probably restricted because of the existence of the crash report data. Here's the relevant comment:

The sequence of calls to NameBuffer in CodeEventLogger::CodeCreateEvent is:

• AppendString(String::cast(source))
• AppendByte(':')
• AppendInt(line)

After the above patch, the utf16buffer used within AppendString() is large enough that copying its contents over to the utf8buffer can fill up the latter. AppendByte() properly checks for that and returns. AppendInt() calls SNPrintF() with a zero-length buffer (because there are zero remaining bytes in utf8buffer), which makes vsnprintf_s() rather unhappy: it calls the InvalidParameter handler which triggers a crash.

CI (just in case): https://ci.nodejs.org/job/node-test-pull-request/442/

LGTM

landed in a334ddc