UserAgent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.94 Safari/537.36

Steps to reproduce the problem:
1. use webpack to compile and uglify the code
2. use source-map to display the source code in dev-tools
3. this will be undefined in a promise

What is the expected behavior?

What went wrong?
dev-tools can not resolve 'this' correctly

Did this work before? N/A 

Chrome version: 62.0.3202.94  Channel: stable
OS Version: 6.1 (Windows 7, Windows Server 2008 R2)
Flash Version: 

pictures here:
https://stackoverflow.com/questions/47530878/why-chrome-dev-tools-cant-reflect-this-correctly-in-a-promise