[FEATURE] Add lastModified and filesize to Resource (Revision 1)

Resource instances now have getFilesize() and getLastModified() methods.

Change-Id: Id91ecca2c8d6a89f542f4431264f1e3b0efb7f3c
Releases: master
Resolves: #49137
Related: #45003
Revision-Id: ce6ab9daede70085a5d4c20ad7ec2cdecaefdf4c