Adding perf testing for brightness and display state changes

The intention is to leverage this test by tracking some internal perfetto
traces, and track the performance of
DisplayPowerController#updatePowerState function

Bug: 249463108
Test: atest DisplayPerfTest
Change-Id: Ia58a170e2b4ae42938a3df9f47baa79dc0866b20

apct-tests/perftests/core/Android.bp

@@ -43,6 +43,7 @@ android_test {
         "apct-perftests-resources-manager-apps",
         "apct-perftests-utils",
         "collector-device-lib",
+        "compatibility-device-util-axt",
         "core-tests-support",
         "guava",
     ],

apct-tests/perftests/core/AndroidManifest.xml

@@ -13,7 +13,9 @@
     <uses-permission android:name="android.permission.INTERACT_ACROSS_USERS" />
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.VIBRATE" />
-
+    <uses-permission android:name="android.permission.DEVICE_POWER" />
+    <uses-permission android:name="android.permission.CONTROL_DISPLAY_BRIGHTNESS" />
+    <uses-permission android:name="android.permission.WRITE_SETTINGS" />
     <application>
         <uses-library android:name="android.test.runner" />
         <profileable android:shell="true" />

apct-tests/perftests/core/src/android/os/DisplayPerfTest.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2022 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.os;
+
+import android.content.Context;
+import android.hardware.display.DisplayManager;
+import android.provider.Settings;
+import android.view.Display;
+
+import androidx.benchmark.BenchmarkState;
+import androidx.benchmark.junit4.BenchmarkRule;
+import androidx.test.platform.app.InstrumentationRegistry;
+import androidx.test.runner.AndroidJUnit4;
+
+import com.android.compatibility.common.util.PollingCheck;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@RunWith(AndroidJUnit4.class)
+public final class DisplayPerfTest {
+    private static final float DELTA = 0.001f;
+
+    @Rule
+    public final BenchmarkRule mBenchmarkRule = new BenchmarkRule();
+
+    private DisplayManager mDisplayManager;
+    private Context mContext;
+
+    @Before
+    public void setUp() {
+        mContext = InstrumentationRegistry.getInstrumentation().getTargetContext();
+        mDisplayManager = mContext.getSystemService(DisplayManager.class);
+    }
+
+    @Test
+    public void testBrightnessChanges() throws Exception {
+        final BenchmarkState state = mBenchmarkRule.getState();
+        Settings.System.putInt(mContext.getContentResolver(),
+                Settings.System.SCREEN_BRIGHTNESS_MODE,
+                Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);
+        SystemClock.sleep(20);
+        float brightness = 0.3f;
+        while (state.keepRunning()) {
+            setAndWaitToChangeBrightness(brightness);
+            brightness = toggleBrightness(brightness);
+        }
+    }
+
+    private float toggleBrightness(float oldBrightness) {
+        float[] brightnesses = new float[]{0.3f, 0.5f};
+        if (oldBrightness == brightnesses[0]) {
+            return brightnesses[1];
+        }
+        return brightnesses[0];
+    }
+
+    private void setAndWaitToChangeBrightness(float brightness) throws Exception {
+        mDisplayManager.setBrightness(0, brightness);
+        PollingCheck.check("Brightness is not set to the expected value", 500,
+                () -> isInRange(mDisplayManager.getBrightness(Display.DEFAULT_DISPLAY), brightness,
+                        DELTA));
+    }
+
+    private boolean isInRange(float value, float target, float delta) {
+        return target - delta <= value && target + delta >= value;
+    }
+}