WebRTC分支提交记录

　　截至2019.8.6日，webrtc官网release了M76，具体可参考：release notes

　　WebRTC分支提交记录能够查看git commit记录。

　　方法：git checkout 到特定分支，使用git log命令查看最上面的提交记录即为该分支最后的提交记录。

remotes/branch-heads/70	4ab51cb6d7d4530b344e63ed8274d1454b7a5f39
remotes/branch-heads/71	0ba24191ee90c70679d2452363676c2d65b6b751
remotes/branch-heads/72	80865776cf8a1a811166ee005951b7f5b01deacd
remotes/branch-heads/m73	8bb9968c6c8643b108e1e972bf77256a97588890
remotes/branch-heads/m74	cc1b32545db7823b85f5a83a92ed5f85970492c9
remotes/branch-heads/M75	159c16f3ceea1d02d08d51fc83d843019d773ec6
remotes/branch-heads/m76	9863f3d246e2da7a2e1f42bbc5757f6af5ec5682
remotes/branch-heads/m77	ad73985e75684cb4ac4dadb9d3d86ad0d66612a0
remotes/branch-heads/m78	...

　　进行同步时，能够指定特定分支。如需同步M74分支：

# gclient sync -r cc1b32545db7823b85f5a83a92ed5f85970492c9