Spacewar: Use overlay instead of property to enable WiFi display

Change-Id: I755c2d94747df53f806a2b834548fb676a23dac0

overlay/frameworks/base/core/res/res/values/config.xml

@@ -57,6 +57,20 @@
     <!-- Maximum color temperature, in Kelvin, supported by display white balance. -->
     <integer name="config_displayWhiteBalanceColorTemperatureMax">7794</integer>
 
+    <!-- Whether WiFi display is supported by this device.
+         There are many prerequisites for this feature to work correctly.
+         Here are a few of them:
+         * The WiFi radio must support WiFi P2P.
+         * The WiFi radio must support concurrent connections to the WiFi display and
+           to an access point.
+         * The Audio Server audio_policy_configuration.xml file must specify a rule for
+           the "r_submix" remote submix module.  This module is used to record and stream system
+           audio output to the WiFi display encoder in the media server.
+         * The remote submix module "audio.r_submix.default" must be installed on the device.
+         * The device must be provisioned with HDCP keys (for protected content).
+    -->
+    <bool name="config_enableWifiDisplay">true</bool>
+
     <!-- Set to true if the wifi display supports compositing content stored
          in gralloc protected buffers.  For this to be true, there must exist
          a protected hardware path for surface flinger to composite and send

properties/system.prop

@@ -61,9 +61,6 @@ persist.timed.enable=true
 # Vendor
 ro.vendor.qti.va_aosp.support=1
 
-# WiFi Display
-persist.debug.wfd.enable=1
-
 # Nt Feature
 ro.build.nothing.feature.base=0x4458438124a040126b4247b97ffL
 ro.build.nothing.feature.diff.device.Spacewar=0x8a0042a4041a032c34800L