Actually, you know, return the timeout

self.getTimeout isn't any good without a return statement.

Change-Id: Icd62967043df7ac69ec706440eafba66049b0052
diff --git a/zuul/cmd/migrate.py b/zuul/cmd/migrate.py
index 92b5963..1b2e44e 100644
--- a/zuul/cmd/migrate.py
+++ b/zuul/cmd/migrate.py
@@ -507,15 +507,19 @@
             self.jjb_job = jobs[self.orig]
 
     def getTimeout(self):
+        timeout = None
         if self.jjb_job:
             for wrapper in self.jjb_job.get('wrappers', []):
                 if isinstance(wrapper, dict):
-                    build_timeout = wrapper.get('timeout')
+                    build_timeout = wrapper.get(
+                        'build-timeout', wrapper.get('timeout'))
                     if isinstance(build_timeout, dict):
                         timeout = build_timeout.get('timeout')
                         if timeout is not None:
                             timeout = int(timeout) * 60
 
+        return timeout
+
     @property
     def short_name(self):
         return self.name.replace('legacy-', '')
@@ -845,9 +849,11 @@
 
         if self.vars:
             output['vars'] = self.vars.copy()
+
         timeout = self.getTimeout()
         if timeout:
             output['timeout'] = timeout
+            output.setdefault('vars', {})
             output['vars']['BUILD_TIMEOUT'] = str(timeout * 1000)
 
         if self.nodes: