Restore fireperf smoke tests as #2158 is fixed.

firebase-database/src/main/java/com/google/firebase/database/Query.java

@@ -163,8 +163,8 @@ public ChildEventListener addChildEventListener(@NonNull ChildEventListener list
   }
 
   /**
-   * Gets the server values for this query. Updates the cache and raises events if successful. If not
-   * connected, falls back to a locally-cached value.
+   * Gets the server values for this query. Updates the cache and raises events if successful. If
+   * not connected, falls back to a locally-cached value.
    */
   @NonNull
   public Task<DataSnapshot> get() {

smoke-tests/build.gradle

@@ -73,8 +73,7 @@ dependencies {
   // TODO(yifany): Restore after messaging in github is up to date
   // implementation "com.google.firebase:firebase-messaging"
   implementation "com.google.firebase:firebase-ml-vision"
-  // TODO(b/174858514): Restore after M85 release is live
-  // implementation "com.google.firebase:firebase-perf"
+  implementation "com.google.firebase:firebase-perf"
   implementation "com.google.firebase:firebase-storage"
 
   // Common utilities (application side)

smoke-tests/src/main/java/com/google/firebase/testing/PerformanceMonitoringTest.java

@@ -0,0 +1,61 @@
+// Copyright 2020 Google LLC
+//
+// 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 com.google.firebase.testing;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import androidx.test.runner.AndroidJUnit4;
+import com.google.firebase.perf.FirebasePerformance;
+import com.google.firebase.perf.metrics.HttpMetric;
+import com.google.firebase.perf.metrics.Trace;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@RunWith(AndroidJUnit4.class)
+public final class PerformanceMonitoringTest {
+
+  @Test
+  public void trace() {
+    Trace trace = FirebasePerformance.getInstance().newTrace("test_trace");
+    trace.start();
+
+    trace.putMetric("counter", 1);
+    trace.incrementMetric("counter", 2);
+    trace.putAttribute("is_test", "true");
+
+    trace.stop();
+
+    assertThat(trace.getLongMetric("counter")).isEqualTo(3);
+    assertThat(trace.getAttribute("is_test")).isEqualTo("true");
+  }
+
+  @Test
+  public void networkRequest() {
+    HttpMetric networkRequest =
+        FirebasePerformance.getInstance()
+            .newHttpMetric("https://www.google.com", FirebasePerformance.HttpMethod.GET);
+    networkRequest.start();
+
+    networkRequest.setRequestPayloadSize(128);
+    networkRequest.setResponsePayloadSize(1024);
+    networkRequest.setHttpResponseCode(200);
+    networkRequest.setResponseContentType("text/html");
+    networkRequest.putAttribute("is_test", "true");
+
+    networkRequest.stop();
+
+    assertThat(networkRequest.getAttribute("is_test")).isEqualTo("true");
+  }
+}