WebRTC: Remove Valgrind based FYI bots.

masters/master.client.webrtc.fyi/slaves.cfg

Index: masters/master.client.webrtc.fyi/slaves.cfg
diff --git a/masters/master.client.webrtc.fyi/slaves.cfg b/masters/master.client.webrtc.fyi/slaves.cfg
index 0dd1eb9110e0abfb5dc6eef2348027a6003c7a7d..e381668b3ef98970cc603449b66a72573c7eae77 100644
--- a/masters/master.client.webrtc.fyi/slaves.cfg
+++ b/masters/master.client.webrtc.fyi/slaves.cfg
@@ -11,24 +11,9 @@ slaves = [
     'bits': '64',
     'builder': [
       'Linux LSan (and ASan)',
-      'Linux TsanRV',
     ],
-    'hostname': 'vm%d-m3' % i,
-  } for i in [4, 31]
-] + [
-  # Mac
-  {
-    'master': 'WebRTCFYI',
-    'os': 'mac',
-    'version': '10.6',  # Notice 10.6 due to lack of Valgrind support on newer.
-    'bits': '64',
-    'builder': [
-      'Mac 10.6 Memcheck',
-      'Mac 10.6 TSan',
-    ],
-    'hostname': 'vm%d-m3' % i,
-  } for i in [653, 665]
-] + [
+    'hostname': 'vm31-m3',
+  },
   # Windows
   {
     'master': 'WebRTCFYI',
@@ -38,6 +23,6 @@ slaves = [
     'builder': [
       'Win Tsan',
     ],
-    'hostname': 'vm%d-m3' % i,
-  } for i in [193]
+    'hostname': 'vm193-m3',
+  }
 ]