test(mbt): Reset timeout events after a failure

Once the node crashes or restarts, it should have no knowledge of past
timeouts that occurred. We missed this detail in the original
specification.

This patch makes sure to reset local events for the failing node.

Author: erickpintor

specs/emerald.qnt

@@ -593,35 +593,31 @@ module emerald {
           }
         }
       | RecordAction(action_taken) =>
-          val ext = {
+          val ext0 = {
             ...ctx.extensions,
             action_taken: action_taken
           }
-
-          val ext0 = match action_taken {
+          match action_taken {
             | Failure(args) =>
                 val { node, height, mode } = args
                 val s = ctx.system.get(node)
                 {
-                  ...ext,
-                  failures: ext.failures.setAdd(args),
-                  // Note that during a node crash, the node loses track of its
-                  // last decided height and restarts from genesis.
-                  last_decided_height:
-                    if (mode == NodeCrash)
-                      ext.last_decided_height.put(node, 0)
-                    else
-                      ext.last_decided_height
+                  ...ctx,
+                  extensions: {
+                    ...ext0,
+                    failures: ext0.failures.setAdd(args),
+                    // Note that during a node crash, the node loses track of its
+                    // last decided height and restarts from genesis.
+                    last_decided_height:
+                      if (mode == NodeCrash) ext0.last_decided_height.put(node, 0)
+                      else ext0.last_decided_height
+                  },
+                  // Note that after a crash/restart the node loses its timeouts.
+                  events:
+                    if (mode != ConsensusTimeout) ctx.events.put(node, Set())
+                    else ctx.events
                 }
-            | _ => ext
-          }
-
-          {
-            ...ctx,
-            extensions: {
-              ...ext0,
-              action_taken: action_taken
-            }
+            | _ => { ...ctx, extensions: ext0 }
           }
     }
   }