Convert most Chromium presubmit files to use new multiple-tryserver-compatible protocol

net/PRESUBMIT.py

Index: net/PRESUBMIT.py
diff --git a/net/PRESUBMIT.py b/net/PRESUBMIT.py
index 3a2f21323b6c7f844a6044305c539b01391194d3..4c0ac24cc11ab9e96371f44d24cc8f4ac6112d78 100644
--- a/net/PRESUBMIT.py
+++ b/net/PRESUBMIT.py
@@ -8,14 +8,17 @@ See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
 for more details on the presubmit API built into gcl.
 """
 
-def GetPreferredTrySlaves(project, change):
-  slaves = [
-    'linux_rel:sync_integration_tests',
-    'mac_rel:sync_integration_tests',
-    'win_rel:sync_integration_tests',
-  ]
+def GetPreferredTryMasters(project, change):
+  masters = {
+    'tryserver.chromium': {
+      'linux_rel': set(['sync_integration_tests']),
+      'mac_rel': set(['sync_integration_tests']),
+      'win_rel': set(['sync_integration_tests']),
+    }
+  }
   # Changes that touch NSS files will likely need a corresponding OpenSSL edit.
   # Conveniently, this one glob also matches _openssl.* changes too.
   if any('nss' in f.LocalPath() for f in change.AffectedFiles()):
-    slaves.append('linux_redux')
-  return slaves
+    masters['tryserver.chromium'].setdefault(
+      'linux_redux', set()).add('defaulttests')
+  return masters