[BUGFIX release] Fix cacheValuePrefix Error

[jmurphyau]

Fixed an issue where cacheValuePrefix would incorrectly check "valA in valB" where valB would be null

Fixes #11857

[rwjblue]

Looks good, can you prefix the commit and PR description with [BUGFIX release]?

[mike-north]

awesome

[jmurphyau]

Didn't notice the failing tests.. Fixing that now

[rwjblue]

Thank you!

[novtor]

Not sure if it is related but starting from 1.13.8 I experience some problems with query parameters. I have following scenario:
parentRoute, childRoute1, childRoute2
parentRoute has queryParams, children do not. When transitionning between children routes, the parentRoute looses its queryParams. The workaround I found (it was a greate chance) is to transition with parentRoute queryParams all set to null -(((. Not sure to understand the logic.
So the working scenrio is:
from childRoute1:

this.transitionTo('childRoute2', {queryParams: {
  parentRouteQP1: null,
  parentRouteQP2: null,
  ....
}});

But before, just

this.transitionTo('childRoute2')

used to work.
Could you investigate on it please.