router.history.previousLocation undefined at ensureConfigured() resolution.

I'm submitting a bug report

Library Version:
1.0.8

Operating System:
Windows 10

Node Version:
6.10.2

NPM Version:
3.10.10

JSPM

Browser:
Chrome 58.0.3029.110 (64-bit)

Language:
JavaScript

Current behavior:
**router.history.previousLocation** is undefined at time **ensureConfigured()** is resolved.

Expected/desired behavior:
Since I'm getting my routes via http I need to ensure refresh is working properly. I have one fallback route which is used while I get my routes and build the router. I expected to use **ensureConfigured()**
to navigate to previous location if it existed in case of refresh.

Start by tracing the router.history.previousLocation value through ensureConfigured(), especially when routes are loaded over HTTP and the router is built. Reproduce the refresh scenario with the fallback route in the reported Aurelia 1.0.8 environment, then verify that the previous location is available when ensureConfigured() resolves and can be used for navigation.

Written by the indexing model from the issue text.