PVS-Studio warning V637 for Chromium

static void ParseRequestCookieLine(
    const std::string& header_value,
    ParsedRequestCookies* parsed_cookies)
{
  std::string::const_iterator i = header_value.begin();
  ....
  if (*i == '"') {
    while (i != header_value.end() && *i != '"') ++i;
  ....
}

This suspicious code was found in Chromium project by PVS-Studio static code analyzer.
Warning message is:
V637 Two opposite conditions were encountered. The second condition is always false. Check lines: 500, 501. web_request_api_helpers.cc 500

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