Add additional methods for manipulating timed transition maps

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130311938

javatests/google/registry/flows/BUILD

@@ -25,6 +25,7 @@ java_library(
     ]),
     resources = glob(["**/testdata/*.xml"]),
     deps = [
+        "//java/com/google/common/annotations",
         "//java/com/google/common/base",
         "//java/com/google/common/collect",
         "//java/com/google/common/io",

javatests/google/registry/model/domain/TestExtraLogicManager.java

@@ -30,7 +30,7 @@ import org.joda.time.DateTime;
 public class TestExtraLogicManager implements RegistryExtraFlowLogic {
 
   @Override
-  public List<String> getFlags(
+  public List<String> getExtensionFlags(
       DomainResource domainResource, String clientIdentifier, DateTime asOfDate) {
     // Take the part before the period, split by dashes, and treat each part after the first as
     // a flag.