Gatekeeper: Add new bots to client.webrtc
Gatekeeper: Add new bots to client.webrtc

New GN bots, iOS ARM64 and a renamed Android ARM64
Builder.

Review URL: https://codereview.chromium.org/950283003

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@294259 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build