UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/603.3.8 (KHTML, like Gecko) Version/10.1.2 Safari/603.3.8

Steps to reproduce the problem:
Chrome: M65

requestIntercepted reports referer in lower case, whereas requestWillBeSent does in capitalized format:
1. Enable request interception by setRequestInterception
2. Modify headers by setExtraHTTPHeaders
3. Observe requestIntercepted and requestWillBeSent's events

Observed with puppeteer: https://github.com/GoogleChrome/puppeteer/issues/1729

What is the expected behavior?
Both events should report referers in same manner.
Capitalized format is desired since other headers are also capitalized.

What went wrong?
requestIntercepted:
{ 'Upgrade-Insecure-Requests': '1',
  'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3312.0 Safari/537.36',
  'X-DevTools-Emulate-Network-Conditions-Client-Id': '2F582D52AEAB3A2AE0919A2FA613CAF6',
  referer: 'http://example.com/',
  Accept: 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8' }

requestWillBeSent:
{ 'Upgrade-Insecure-Requests': '1',
  Referer: 'http://example.com/',
  'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3312.0 Safari/537.36' }

Did this work before? N/A 

Chrome version: 65.0.3312.0  Channel: n/a
OS Version: OS X 10.10.5
Flash Version: Shockwave Flash 28.0 r0
 

Deleted: example.js 1.3 KB

example.js 1.3 KB View Download