Fix some issues caught by IntelliJ static code analysis

The most common issues were:
* Arrays.asList() shouldn't be called with a single parameter.
* Broken Javadoc @links.
* Unnecessary casts and type declarations.
* Unnecessary unused variable initializations.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=230994311

javatests/google/registry/testing/AppEngineRule.java

@@ -290,11 +290,13 @@ public final class AppEngineRule extends ExternalResource {
 
     if (withUserService) {
       // Set top-level properties on LocalServiceTestConfig for user login.
-      helper.setEnvIsLoggedIn(userInfo.isLoggedIn())
+      helper
+          .setEnvIsLoggedIn(userInfo.isLoggedIn())
           // This envAttributes thing is the only way to set userId.
           // see https://code.google.com/p/googleappengine/issues/detail?id=3579
-          .setEnvAttributes(ImmutableMap.<String, Object>of(
-              "com.google.appengine.api.users.UserService.user_id_key", userInfo.gaeUserId()))
+          .setEnvAttributes(
+              ImmutableMap.of(
+                  "com.google.appengine.api.users.UserService.user_id_key", userInfo.gaeUserId()))
           .setEnvAuthDomain(userInfo.authDomain())
           .setEnvEmail(userInfo.email())
           .setEnvIsAdmin(userInfo.isAdmin());