Use config.xml for Flip to Screen Off.

This allows us to disable the feature for specific builds without need for network.

Test: Locally & atest FaceDownDetector
Bug: 185136783
Bug: 184963215
Change-Id: I0c22dcc01aabb9b92cc16f693f7f79755ae256a8

core/res/res/values/config.xml

@@ -1777,6 +1777,9 @@
         <!-- Add algorithm here -->
     </string-array>
 
+    <!-- Boolean indicating if placing the phone face down will result in a screen off. -->
+    <bool name="config_flipToScreenOffEnabled">true</bool>
+
     <!-- Boolean indicating if current platform supports bluetooth SCO for off call
     use cases -->
     <bool name="config_bluetooth_sco_off_call">true</bool>

core/res/res/values/symbols.xml

@@ -275,6 +275,7 @@
   <java-symbol type="bool" name="action_bar_expanded_action_views_exclusive" />
   <java-symbol type="bool" name="config_avoidGfxAccel" />
   <java-symbol type="bool" name="config_bluetooth_address_validation" />
+  <java-symbol type="bool" name="config_flipToScreenOffEnabled" />
   <java-symbol type="bool" name="config_bluetooth_sco_off_call" />
   <java-symbol type="bool" name="config_bluetooth_le_peripheral_mode_supported" />
   <java-symbol type="bool" name="config_bluetooth_hfp_inband_ringing_support" />

services/core/java/com/android/server/power/FaceDownDetector.java

@@ -324,7 +324,9 @@ public class FaceDownDetector implements SensorEventListener {
 
     private boolean isEnabled() {
         return DeviceConfig.getBoolean(NAMESPACE_ATTENTION_MANAGER_SERVICE, KEY_FEATURE_ENABLED,
-                DEFAULT_FEATURE_ENABLED);
+                DEFAULT_FEATURE_ENABLED)
+                && mContext.getResources().getBoolean(
+                        com.android.internal.R.bool.config_flipToScreenOffEnabled);
     }
 
     private float getAccelerationThreshold() {