Add support to the build system for tracking if/when the build manager crashes and make sure builds are restarted within a few minutes

buildman/manager/enterprise.py

@@ -36,6 +36,11 @@ class EnterpriseManager(BaseManager):
     # production, build workers in enterprise are long-lived and register dynamically.
     self.register_component(REGISTRATION_REALM, DynamicRegistrationComponent)
 
+  def setup_time(self):
+    # Builders are already registered, so the setup time should be essentially instant. We therefore
+    # only return a minute here.
+    return 60
+
   def add_build_component(self):
     """ Adds a new build component for an Enterprise Registry. """
     # Generate a new unique realm ID for the build worker.