- Lets InvokeContext::process_cross_program_instruction() handle the first invocation depth too.
- Marks InvokeContext::verify(), InvokeContext::verify_and_update() and InvokeContext::process_executable_chain() private.
- Renames InvokeContext::process_cross_program_instruction() to InvokeContext::process_instruction().
- Removes InvokeContext::new_mock_with_sysvars().
(cherry picked from commit 1df88837c8d11c40bcdf2800ecc4606493bbfd67)
Co-authored-by: Alexander Meißner <AlexanderMeissner@gmx.net>