Is your feature request related to a problem? Please describe.
This is part of a series of issues related to cleaning up the integration tests. We currently have an OVMMulticall.sol contract within the integration tests that could be replaced with a cleaner combination of two distinct contracts.

Describe the solution you'd like
I recommend that we replace OVMMulticall.sol with two contracts, the standard Multicall.sol contract and a separate new OVMContext.sol contract which would contain these functions found within the current OVMMulticall.sol contract. I don't see a good reason why these functions are part of the Multicall contract. If we put these functions in a separate contract, then we can also reuse the functions inside of OVMContextStorage.sol.