Developer settings: Disable wifi scan throttling

Add a new developer settings toggle to allow users to
toggle wifi scan throttling off.

Bug: 112825565
Test: atest com.android.settings.development
Test: Manual verification of the new switch.
Change-Id: I1d8c149305ca92957c7d1b9f28497291ca8b2bf7
diff --git a/res/xml/development_settings.xml b/res/xml/development_settings.xml
index c537f3f..573bc94 100644
--- a/res/xml/development_settings.xml
+++ b/res/xml/development_settings.xml
@@ -248,6 +248,11 @@
             android:summary="@string/wifi_verbose_logging_summary" />
 
         <SwitchPreference
+            android:key="wifi_scan_throttling"
+            android:title="@string/wifi_scan_throttling"
+            android:summary="@string/wifi_scan_throttling_summary" />
+
+        <SwitchPreference
             android:key="mobile_data_always_on"
             android:title="@string/mobile_data_always_on"
             android:summary="@string/mobile_data_always_on_summary" />
diff --git a/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java b/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java
index 9dcc222..bca5ded 100644
--- a/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java
+++ b/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java
@@ -432,6 +432,7 @@
         controllers.add(new CameraLaserSensorPreferenceController(context));
         controllers.add(new WifiDisplayCertificationPreferenceController(context));
         controllers.add(new WifiVerboseLoggingPreferenceController(context));
+        controllers.add(new WifiScanThrottlingPreferenceController(context));
         controllers.add(new MobileDataAlwaysOnPreferenceController(context));
         controllers.add(new TetheringHardwareAccelPreferenceController(context));
         controllers.add(new BluetoothDeviceNoNamePreferenceController(context));
diff --git a/src/com/android/settings/development/WifiScanThrottlingPreferenceController.java b/src/com/android/settings/development/WifiScanThrottlingPreferenceController.java
new file mode 100644
index 0000000..a069827
--- /dev/null
+++ b/src/com/android/settings/development/WifiScanThrottlingPreferenceController.java
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2019 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 com.android.settings.development;
+
+import android.content.Context;
+import android.provider.Settings;
+
+import androidx.annotation.VisibleForTesting;
+import androidx.preference.Preference;
+import androidx.preference.SwitchPreference;
+
+import com.android.settings.core.PreferenceControllerMixin;
+import com.android.settingslib.development.DeveloperOptionsPreferenceController;
+
+public class WifiScanThrottlingPreferenceController extends DeveloperOptionsPreferenceController
+        implements Preference.OnPreferenceChangeListener, PreferenceControllerMixin {
+    private static final String WIFI_SCAN_THROTTLING_KEY = "wifi_scan_throttling";
+    @VisibleForTesting
+    static final int SETTING_THROTTLING_ENABLE_VALUE_ON = 1;  // default is throttling enabled.
+    @VisibleForTesting
+    static final int SETTING_THROTTLING_ENABLE_VALUE_OFF = 0;
+
+    public WifiScanThrottlingPreferenceController(Context context) {
+        super(context);
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return WIFI_SCAN_THROTTLING_KEY;
+    }
+
+    @Override
+    public boolean onPreferenceChange(Preference preference, Object newValue) {
+        final boolean isEnabled = (Boolean) newValue;
+        Settings.Global.putInt(mContext.getContentResolver(),
+                Settings.Global.WIFI_SCAN_THROTTLE_ENABLED,
+                isEnabled
+                        ? SETTING_THROTTLING_ENABLE_VALUE_ON
+                        : SETTING_THROTTLING_ENABLE_VALUE_OFF);
+        return true;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        final int scanThrottleEnabled = Settings.Global.getInt(
+                mContext.getContentResolver(), Settings.Global.WIFI_SCAN_THROTTLE_ENABLED,
+                SETTING_THROTTLING_ENABLE_VALUE_ON);
+        ((SwitchPreference) mPreference).setChecked(
+                scanThrottleEnabled == SETTING_THROTTLING_ENABLE_VALUE_ON);
+    }
+
+    @Override
+    protected void onDeveloperOptionsSwitchDisabled() {
+        super.onDeveloperOptionsSwitchDisabled();
+        Settings.Global.putInt(mContext.getContentResolver(),
+                Settings.Global.WIFI_SCAN_THROTTLE_ENABLED, SETTING_THROTTLING_ENABLE_VALUE_ON);
+        ((SwitchPreference) mPreference).setChecked(true);
+    }
+}
diff --git a/tests/robotests/src/com/android/settings/development/WifiScanThrottlingPreferenceControllerTest.java b/tests/robotests/src/com/android/settings/development/WifiScanThrottlingPreferenceControllerTest.java
new file mode 100644
index 0000000..605bd0d
--- /dev/null
+++ b/tests/robotests/src/com/android/settings/development/WifiScanThrottlingPreferenceControllerTest.java
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2019 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 com.android.settings.development;
+
+import static com.android.settings.development.WifiScanThrottlingPreferenceController.SETTING_THROTTLING_ENABLE_VALUE_OFF;
+import static com.android.settings.development.WifiScanThrottlingPreferenceController.SETTING_THROTTLING_ENABLE_VALUE_ON;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.provider.Settings;
+
+import androidx.preference.PreferenceScreen;
+import androidx.preference.SwitchPreference;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.RuntimeEnvironment;
+
+@RunWith(RobolectricTestRunner.class)
+public class WifiScanThrottlingPreferenceControllerTest {
+
+    @Mock
+    private SwitchPreference mPreference;
+    @Mock
+    private PreferenceScreen mPreferenceScreen;
+
+    private Context mContext;
+    private WifiScanThrottlingPreferenceController mController;
+
+    @Before
+    public void setup() {
+        MockitoAnnotations.initMocks(this);
+        mContext = RuntimeEnvironment.application;
+        mController = new WifiScanThrottlingPreferenceController(mContext);
+        when(mPreferenceScreen.findPreference(mController.getPreferenceKey()))
+                .thenReturn(mPreference);
+        mController.displayPreference(mPreferenceScreen);
+    }
+
+    @Test
+    public void onPreferenceChanged_turnOnScanThrottling() {
+        mController.onPreferenceChange(mPreference, true /* new value */);
+
+        final int mode = Settings.Global.getInt(mContext.getContentResolver(),
+                Settings.Global.WIFI_SCAN_THROTTLE_ENABLED, 1 /* default */);
+
+        assertThat(mode).isEqualTo(SETTING_THROTTLING_ENABLE_VALUE_ON);
+    }
+
+    @Test
+    public void onPreferenceChanged_turnOffScanThrottling() {
+        mController.onPreferenceChange(mPreference, false /* new value */);
+
+        final int mode = Settings.Global.getInt(mContext.getContentResolver(),
+                Settings.Global.WIFI_SCAN_THROTTLE_ENABLED, 1 /* default */);
+
+        assertThat(mode).isEqualTo(SETTING_THROTTLING_ENABLE_VALUE_OFF);
+    }
+
+    @Test
+    public void updateState_preferenceShouldBeChecked() {
+        Settings.Global.putInt(mContext.getContentResolver(),
+                Settings.Global.WIFI_SCAN_THROTTLE_ENABLED,
+                SETTING_THROTTLING_ENABLE_VALUE_ON);
+        mController.updateState(mPreference);
+
+        verify(mPreference).setChecked(true);
+    }
+
+    @Test
+    public void updateState_preferenceShouldNotBeChecked() {
+        Settings.Global.putInt(mContext.getContentResolver(),
+                Settings.Global.WIFI_SCAN_THROTTLE_ENABLED,
+                SETTING_THROTTLING_ENABLE_VALUE_OFF);
+        mController.updateState(mPreference);
+
+        verify(mPreference).setChecked(false);
+    }
+
+    @Test
+    public void onDeveloperOptionsDisabled_shouldDisablePreference() {
+        mController.onDeveloperOptionsDisabled();
+        final int mode = Settings.Global.getInt(mContext.getContentResolver(),
+                Settings.Global.WIFI_SCAN_THROTTLE_ENABLED, 1 /* default */);
+
+        assertThat(mode).isEqualTo(SETTING_THROTTLING_ENABLE_VALUE_ON);
+        verify(mPreference).setEnabled(false);
+        verify(mPreference).setChecked(true);
+    }
+}