Adding performance to firebase-exp (#3830)

* Adding performance and installations to firebase-exp

* Adding a missing param doc

* Updating Copyright date to 2020

* Reverting the changes to installations

* Updating performance/package.json to use the correct distributions

Author: jposuna

packages-exp/firebase-exp/package.json

@@ -40,7 +40,8 @@
     "@firebase/app-exp": "0.0.800",
     "@firebase/app-compat": "0.0.800",
     "@firebase/functions-exp": "0.0.800",
-    "@firebase/firestore": "1.17.0"
+    "@firebase/firestore": "1.17.0",
+    "@firebase/performance-exp": "0.0.800"
   },
   "devDependencies": {
     "rollup": "2.28.1",
@@ -60,6 +61,7 @@
     "app",
     "functions",
     "firestore",
-    "firestore/lite"
+    "firestore/lite",
+    "performance"
   ]
 }

packages-exp/firebase-exp/performance/index.ts

@@ -0,0 +1,17 @@
+/**
+ * @license
+ * 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.
+ */
+export * from '@firebase/performance-exp';

packages-exp/firebase-exp/performance/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "firebase-exp/performance",
+  "main": "dist/index.cjs.js",
+  "browser": "dist/index.esm.js",
+  "module": "dist/index.esm.js",
+  "typings": "dist/index.d.ts"
+}

packages-exp/performance-exp/src/resources/trace.ts

@@ -57,6 +57,7 @@ export class Trace implements PerformanceTrace {
   private traceMeasure!: string;
 
   /**
+   * @param performanceController The performance controller running.
    * @param name The name of the trace.
    * @param isAuto If the trace is auto-instrumented.
    * @param traceMeasureName The name of the measure marker in user timing specification. This field