[FIX] ODataModel: Properly handle empty query string

If the OData service URL had an empty query string, this caused empty query
strings to be attached to all requests or made the metadata request fail in
the V2 model.

Change-Id: I37f8a661c94b14e3f42df330b69af26e2966c547
[INTERNAL] clean up and unify scrolling behavior

- all supported platforms use native scrolling now
- remove redundand div in the layout of sap.m.Page
- remove redundant scrolling related code
- adjust qUnits

Change-Id: I06296588b09b6aec81478651e882b87bb51aad1e
Merge "[INTERNAL] clean up and unify scrolling behavior"
Merge "[FIX] ODataModel: Properly handle empty query string"