Also changed from unsigned to signed integer per the style guide. By the way, I kept all delta-times to be 32-bit int. The only things left in the p2p dir are 1. proberprober/main.cc where Time() is used as the input for a random number. 2. pseudotcp.cc: where 32-bit time info is sent over the wire. BUG=webrtc:5636 Review URL: https://codereview.webrtc.org/1793553002 Cr-Commit-Position: refs/heads/master@{#12019}