Router should not mutate Route config objects because it causes issue with platform-server

[vikerman]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[x] Bug report  
[ ] Feature request
[ ] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead see https://github.com/angular/angular/blob/master/CONTRIBUTING.md#question

Current behavior

Router mutates Route[] object created by the user and configure in NgModule by writing extra _loadedConfig field.

This is ok for platform-browser by not for platform-server where parallel requests are sharing the same Route[] object.

Expected behavior

Router should create a copy of the Route config per application before mutating it.

Minimal reproduction of the problem with instructions

What is the motivation / use case for changing the behavior?

This is to make sure Router works properly on the server environment

Environment

Angular version: latest

For Tooling issues:
any

Others:
-

[Longfld]

Hi,
that change breaks my current application,.
Could you please give a sample, how we should use it after your changes?
This is not suppose to be breaking changes

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