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:
In index source map, every section have either "map" or "url" property.
ATM devtools support only "map" property.

In case of "url" property, the sourcemap for the section should be downloaded from that url.

SourceMap spec: https://goo.gl/vtEVF

What is the expected behavior?
Chrome supports the spec as written by Google.

What went wrong?
The source map does not work. The error message is not helpful.

Did this work before? No 

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

This was originally filed as https://bugs.chromium.org/p/chromium/issues/detail?id=552455. The maintainers asked that it be re-filed with justification since work on it is not planned.

Why I think this is important:
* I wasted quite a bit of time trying to debug my sourcemaps because Chrome does not comply with the spec and gives no obvious error. I am sure that this has happened to other devs as well and will continue to happen.
* Our codebase still contains a workaround for this which makes our sourcemaps larger and more complex than they would be otherwise.
* Not knowing the Chrome codebase at all, it feels like this should be a relatively minor fix without broad implications. 
* Even a minor change to report the specific cause of failure would be a significant improvement; this should be a very inexpensive change.