Changes of eosio.system

static constexpr int64_t ram_gift_bytes = 1400;

1.

2. static constexpr

image.png

3. Function buyram

3.1. inside function buyram and add update_ram_supply()

3.2. N(eosio.ram), N(active)

3.3. set_resource_limits(res_itr->ram_bytes)

ram_gift_bytes

4. Function sellram

4.1 changebw(from, receiver, stake_net_delta, stake_cpu_delta, bool transfer)