resourceloader: Fix mw.loader to compute combined version in packed order
The 'version' param was being computed based on the order of the modules list
before we perform string compression. And this compression can change the order
for its optimisation purposes.
Specifically, when requesting modules like 'a', 'b.1', 'b.2' and 'c'. The
version was computed based on a + b.1 + b.2 + c (standard sort order),
whereas the optimised list is 'a,c|b.1,2', which expands to a + c + b.1 + b.2,
which makes hash validation fail.
Bug: T188076
Change-Id: I00d6985c054fecd88acf73041aa02878e83d62bc