Add unofficial intent for BatterySaverSchedule screen

We need this for some battery features but don't really think it
needs to be a public API.

Test: can call intent, robotests pass
Bug: 129006417
Change-Id: I1362cea392126c72b20a84e1945d7076c5225b33

AndroidManifest.xml

@@ -3136,6 +3136,17 @@
             <meta-data android:name="com.android.settings.FRAGMENT_CLASS"
                 android:value="com.android.settings.wifi.calling.WifiCallingDisclaimerFragment" />
         </activity>
+
+        <activity android:name="Settings$BatterySaverScheduleSettingsActivity"
+            android:label="@string/battery_saver_schedule_settings_title"
+            android:parentActivityName="Settings">
+            <intent-filter>
+                <action android:name="com.android.settings.BATTERY_SAVER_SCHEDULE_SETTINGS" />
+                <category android:name="android.intent.category.DEFAULT" />
+            </intent-filter>
+            <meta-data android:name="com.android.settings.FRAGMENT_CLASS"
+                android:value="com.android.settings.fuelgauge.batterysaver.BatterySaverScheduleSettings" />
+        </activity>
         <!-- This is the longest AndroidManifest.xml ever. -->
     </application>
 </manifest>

src/com/android/settings/Settings.java

@@ -77,6 +77,7 @@ public class Settings extends SettingsActivity {
     public static class FactoryResetActivity extends SettingsActivity { /* empty */ }
     public static class RunningServicesActivity extends SettingsActivity { /* empty */ }
     public static class BatterySaverSettingsActivity extends SettingsActivity { /* empty */ }
+    public static class BatterySaverScheduleSettingsActivity extends SettingsActivity { /* empty */ }
     public static class AccountSyncSettingsActivity extends SettingsActivity { /* empty */ }
     public static class AccountSyncSettingsInAddAccountActivity extends SettingsActivity { /* empty */ }
     public static class CryptKeeperSettingsActivity extends SettingsActivity { /* empty */ }

src/com/android/settings/core/gateway/SettingsGateway.java

@@ -75,6 +75,7 @@ import com.android.settings.dream.DreamSettings;
 import com.android.settings.enterprise.EnterprisePrivacySettings;
 import com.android.settings.fuelgauge.AdvancedPowerUsageDetail;
 import com.android.settings.fuelgauge.PowerUsageSummary;
+import com.android.settings.fuelgauge.batterysaver.BatterySaverScheduleSettings;
 import com.android.settings.fuelgauge.batterysaver.BatterySaverSettings;
 import com.android.settings.gestures.AssistGestureSettings;
 import com.android.settings.gestures.DoubleTapPowerSettings;
@@ -270,6 +271,7 @@ public class SettingsGateway {
             DataUsageList.class.getName(),
             ToggleBackupSettingFragment.class.getName(),
             PreviouslyConnectedDeviceDashboardFragment.class.getName(),
+            BatterySaverScheduleSettings.class.getName()
     };
 
     public static final String[] SETTINGS_FOR_RESTRICTED = {