Fixes a minor bug in type variable generation (#5795)
Fixes a minor bug in type variable generation (#5795)

We should be comparing variable names for equality, not for substring inclusion.
PolymerLabs/arcs,PolymerLabs/arcs,PolymerLabs/arcs,PolymerLabs/arcs,PolymerLabs/arcs,PolymerLabs/arcs,PolymerLabs/arcs,PolymerLabs/arcs