Add Benchmark for PackageManager.getResourcesForApplication

Add the benchmark for anwsering the performance issue.
* the cost of the createContextAsUser
* the comparsion between *AsUser and createContextAsUser

Test: atest CorePerfTests:android.content.pm.PackageManagerBenchmark
Bug: 171370490
Change-Id: I7da6d4127520c1132c6050472a0c1ba462ab03d3
diff --git a/apct-tests/perftests/core/src/android/content/pm/PackageManagerBenchmark.java b/apct-tests/perftests/core/src/android/content/pm/PackageManagerBenchmark.java
new file mode 100644
index 0000000..a82fab4
--- /dev/null
+++ b/apct-tests/perftests/core/src/android/content/pm/PackageManagerBenchmark.java
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * 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 android.content.pm;
+
+import android.content.Context;
+import android.os.UserHandle;
+import android.perftests.utils.BenchmarkState;
+import android.perftests.utils.PerfStatusReporter;
+
+import androidx.test.platform.app.InstrumentationRegistry;
+import androidx.test.runner.AndroidJUnit4;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@RunWith(AndroidJUnit4.class)
+public class PackageManagerBenchmark {
+    @Rule
+    public PerfStatusReporter mPerfStatusReporter = new PerfStatusReporter();
+
+    @Test
+    public void createUserContextBenchmark() {
+        Context context = InstrumentationRegistry.getInstrumentation().getTargetContext();
+        final BenchmarkState state = mPerfStatusReporter.getBenchmarkState();
+
+        while (state.keepRunning()) {
+            context.createContextAsUser(UserHandle.SYSTEM, /* flags */ 0);
+        }
+    }
+
+    @Test
+    public void getResourcesForApplication_byStarAsUser()
+            throws PackageManager.NameNotFoundException {
+        Context context = InstrumentationRegistry.getInstrumentation().getTargetContext();
+        final BenchmarkState state = mPerfStatusReporter.getBenchmarkState();
+
+        while (state.keepRunning()) {
+            context.getPackageManager().getResourcesForApplicationAsUser(context.getPackageName(),
+                    UserHandle.USER_SYSTEM);
+        }
+    }
+
+    @Test
+    public void getResourcesApplication_byCreateContextAsUser()
+            throws PackageManager.NameNotFoundException {
+        Context context = InstrumentationRegistry.getInstrumentation().getTargetContext();
+        final BenchmarkState state = mPerfStatusReporter.getBenchmarkState();
+
+        while (state.keepRunning()) {
+            context.createContextAsUser(UserHandle.SYSTEM, /* flags */ 0).getPackageManager()
+                    .getResourcesForApplication(context.getPackageName());
+        }
+    }
+}