Move GCP proxy code to the old [] proxy's location

1. Moved code for the GCP proxy to where the [] proxy code used to live.
3. Corrected reference to the GCP proxy location.
4. Misc changes to make ErrorProne and various tools happy.

+diekmann to LGTM terraform whitelist change.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=213630560

javatests/google/registry/proxy/quota/QuotaManagerTest.java

@@ -0,0 +1,82 @@
+// Copyright 2017 The Nomulus Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.proxy.quota;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.mockito.Matchers.anyString;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.when;
+
+import com.google.common.util.concurrent.MoreExecutors;
+import google.registry.proxy.quota.QuotaManager.QuotaRebate;
+import google.registry.proxy.quota.QuotaManager.QuotaRequest;
+import google.registry.proxy.quota.QuotaManager.QuotaResponse;
+import google.registry.proxy.quota.TokenStore.TimestampedInteger;
+import google.registry.testing.FakeClock;
+import java.util.concurrent.Future;
+import org.joda.time.DateTime;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Unit tests for {@link QuotaManager}. */
+@RunWith(JUnit4.class)
+public class QuotaManagerTest {
+
+  private static final String USER_ID = "theUser";
+
+  private final TokenStore tokenStore = mock(TokenStore.class);
+  private final FakeClock clock = new FakeClock();
+
+  private QuotaManager quotaManager =
+      new QuotaManager(tokenStore, MoreExecutors.newDirectExecutorService());
+  private QuotaRequest request;
+  private QuotaResponse response;
+
+  @Test
+  public void testSuccess_requestApproved() {
+    when(tokenStore.take(anyString())).thenReturn(TimestampedInteger.create(1, clock.nowUtc()));
+
+    request = QuotaRequest.create(USER_ID);
+    response = quotaManager.acquireQuota(request);
+    assertThat(response.success()).isTrue();
+    assertThat(response.userId()).isEqualTo(USER_ID);
+    assertThat(response.grantedTokenRefillTime()).isEqualTo(clock.nowUtc());
+  }
+
+  @Test
+  public void testSuccess_requestDenied() {
+    when(tokenStore.take(anyString())).thenReturn(TimestampedInteger.create(0, clock.nowUtc()));
+
+    request = QuotaRequest.create(USER_ID);
+    response = quotaManager.acquireQuota(request);
+    assertThat(response.success()).isFalse();
+    assertThat(response.userId()).isEqualTo(USER_ID);
+    assertThat(response.grantedTokenRefillTime()).isEqualTo(clock.nowUtc());
+  }
+
+  @Test
+  public void testSuccess_rebate() throws Exception {
+    DateTime grantedTokenRefillTime = clock.nowUtc();
+    response = QuotaResponse.create(true, USER_ID, grantedTokenRefillTime);
+    QuotaRebate rebate = QuotaRebate.create(response);
+    Future<?> unusedFuture = quotaManager.releaseQuota(rebate);
+    verify(tokenStore).scheduleRefresh();
+    verify(tokenStore).put(USER_ID, grantedTokenRefillTime);
+    verifyNoMoreInteractions(tokenStore);
+  }
+}