Remove tests related to duplicate event type registration

which I forgot to remove in eabc8ad3.

Change-Id: If04a644fd626bbfb82e75eed22a93a6d5b4e500a
diff --git a/gerrit-server/src/test/java/com/google/gerrit/server/events/EventTypesTest.java b/gerrit-server/src/test/java/com/google/gerrit/server/events/EventTypesTest.java
index 1073522..7eed35f 100644
--- a/gerrit-server/src/test/java/com/google/gerrit/server/events/EventTypesTest.java
+++ b/gerrit-server/src/test/java/com/google/gerrit/server/events/EventTypesTest.java
@@ -15,7 +15,6 @@
 package com.google.gerrit.server.events;
 
 import static com.google.common.truth.Truth.assertThat;
-import static org.junit.Assert.fail;
 
 import org.junit.Test;
 
@@ -26,12 +25,6 @@
     }
   }
 
-  public static class TestEvent2 extends Event {
-    public TestEvent2() {
-      super("test-event"); // Intentionally same as in TestEvent
-    }
-  }
-
   public static class AnotherTestEvent extends Event {
     public AnotherTestEvent() {
       super("another-test-event");
@@ -45,20 +38,6 @@
     assertThat(EventTypes.getClass("test-event")).isEqualTo(TestEvent.class);
     assertThat(EventTypes.getClass("another-test-event"))
       .isEqualTo(AnotherTestEvent.class);
-
-    try {
-      EventTypes.registerClass(new TestEvent());
-      fail("Expected IllegalArgumentException");
-    } catch (IllegalArgumentException e) {
-      assertThat(EventTypes.getClass("test-event")).isEqualTo(TestEvent.class);
-    }
-
-    try {
-      EventTypes.registerClass(new TestEvent2());
-      fail("Expected IllegalArgumentException");
-    } catch (IllegalArgumentException e) {
-      assertThat(EventTypes.getClass("test-event")).isEqualTo(TestEvent.class);
-    }
   }
 
   @Test