Move premium list static helper methods into their own class

It was kind of messy having all of that logic living alongside the
entities themselves.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148498024

javatests/google/registry/tools/DeletePremiumListCommandTest.java

@@ -17,6 +17,7 @@ package google.registry.tools;
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.common.truth.Truth.assertWithMessage;
 import static google.registry.model.ofy.ObjectifyService.ofy;
+import static google.registry.model.registry.label.PremiumListUtils.loadPremiumListEntries;
 import static google.registry.testing.DatastoreHelper.createTld;
 import static google.registry.testing.DatastoreHelper.persistPremiumList;
 import static google.registry.testing.DatastoreHelper.persistResource;
@@ -32,7 +33,7 @@ public class DeletePremiumListCommandTest extends CommandTestCase<DeletePremiumL
   @Test
   public void testSuccess() throws Exception {
     PremiumList premiumList = persistPremiumList("xn--q9jyb4c", "blah,USD 100");
-    assertThat(premiumList.loadPremiumListEntries()).hasSize(1);
+    assertThat(loadPremiumListEntries(premiumList)).hasSize(1);
     runCommand("--force", "--name=xn--q9jyb4c");
     assertThat(PremiumList.get("xn--q9jyb4c")).isAbsent();
 
@@ -62,7 +63,8 @@ public class DeletePremiumListCommandTest extends CommandTestCase<DeletePremiumL
     } catch (IllegalArgumentException e) {
       assertThat(PremiumList.get(premiumList.getName())).isPresent();
       assertThat(e)
-          .hasMessage("Cannot delete premium list because it is used on these tld(s): xn--q9jyb4c");
+          .hasMessageThat()
+          .isEqualTo("Cannot delete premium list because it is used on these tld(s): xn--q9jyb4c");
     }
   }
 }

javatests/google/registry/tools/server/CreatePremiumListActionTest.java

@@ -15,7 +15,9 @@
 package google.registry.tools.server;
 
 import static com.google.common.truth.Truth.assertThat;
-import static google.registry.model.registry.label.PremiumList.getPremiumPrice;
+import static google.registry.model.registry.label.PremiumListUtils.deletePremiumList;
+import static google.registry.model.registry.label.PremiumListUtils.getPremiumPrice;
+import static google.registry.model.registry.label.PremiumListUtils.loadPremiumListEntries;
 import static google.registry.testing.DatastoreHelper.createTlds;
 import static javax.servlet.http.HttpServletResponse.SC_OK;
 
@@ -37,13 +39,8 @@ import org.junit.runners.JUnit4;
 @RunWith(JUnit4.class)
 public class CreatePremiumListActionTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder()
-      .withDatastore()
-      .build();
-
-  @Rule
-  public final ExceptionRule thrown = new ExceptionRule();
+  @Rule public final AppEngineRule appEngine = AppEngineRule.builder().withDatastore().build();
+  @Rule public final ExceptionRule thrown = new ExceptionRule();
 
   CreatePremiumListAction action;
   FakeJsonResponse response;
@@ -51,7 +48,7 @@ public class CreatePremiumListActionTest {
   @Before
   public void init() throws Exception {
     createTlds("foo", "xn--q9jyb4c", "how");
-    PremiumList.get("foo").get().delete();
+    deletePremiumList(PremiumList.get("foo").get());
     action = new CreatePremiumListAction();
     response = new FakeJsonResponse();
     action.response = response;
@@ -83,7 +80,7 @@ public class CreatePremiumListActionTest {
     action.override = true;
     action.run();
     assertThat(response.getStatus()).isEqualTo(SC_OK);
-    assertThat(PremiumList.get("zanzibar").get().loadPremiumListEntries()).hasSize(1);
+    assertThat(loadPremiumListEntries(PremiumList.get("zanzibar").get())).hasSize(1);
   }
 
   @Test
@@ -92,7 +89,7 @@ public class CreatePremiumListActionTest {
     action.inputData = "rich,USD 25\nricher,USD 1000\n";
     action.run();
     assertThat(response.getStatus()).isEqualTo(SC_OK);
-    assertThat(PremiumList.get("foo").get().loadPremiumListEntries()).hasSize(2);
+    assertThat(loadPremiumListEntries(PremiumList.get("foo").get())).hasSize(2);
     assertThat(getPremiumPrice("rich", Registry.get("foo"))).hasValue(Money.parse("USD 25"));
     assertThat(getPremiumPrice("diamond", Registry.get("foo"))).isAbsent();
   }

javatests/google/registry/tools/server/UpdatePremiumListActionTest.java

@@ -15,7 +15,8 @@
 package google.registry.tools.server;
 
 import static com.google.common.truth.Truth.assertThat;
-import static google.registry.model.registry.label.PremiumList.getPremiumPrice;
+import static google.registry.model.registry.label.PremiumListUtils.getPremiumPrice;
+import static google.registry.model.registry.label.PremiumListUtils.loadPremiumListEntries;
 import static google.registry.testing.DatastoreHelper.createTlds;
 import static javax.servlet.http.HttpServletResponse.SC_OK;
 
@@ -82,7 +83,7 @@ public class UpdatePremiumListActionTest {
     action.run();
     assertThat(response.getStatus()).isEqualTo(SC_OK);
     Registry registry = Registry.get("foo");
-    assertThat(PremiumList.get("foo").get().loadPremiumListEntries()).hasSize(3);
+    assertThat(loadPremiumListEntries(PremiumList.get("foo").get())).hasSize(3);
     assertThat(getPremiumPrice("rich", registry)).hasValue(Money.parse("USD 75"));
     assertThat(getPremiumPrice("richer", registry)).hasValue(Money.parse("USD 5000"));
     assertThat(getPremiumPrice("poor", registry)).hasValue(Money.parse("USD 0.99"));