wifidisplay: restrict broadcast by the proper permission

WIFI_DISPLAY_STATUS_CHANGED event contains the MAC address of peers.
As the MAC address is PII data, this should be restricted by proper
permission.

Bug: 176541017
Test: install PoC in b/176541017 and check PII data is not leaked.
Change-Id: I36b85f44678fe232486702fa009f5f06d1a7af75

core/java/android/hardware/display/DisplayManager.java

@@ -61,6 +61,9 @@ public final class DisplayManager {
      * {@link #EXTRA_WIFI_DISPLAY_STATUS} extra.
      * </p><p>
      * This broadcast is only sent to registered receivers and can only be sent by the system.
+     * </p><p>
+     * {@link android.Manifest.permission#ACCESS_FINE_LOCATION} permission is required to
+     * receive this broadcast.
      * </p>
      * @hide
      */

services/core/java/com/android/server/display/WifiDisplayAdapter.java

@@ -91,6 +91,10 @@ final class WifiDisplayAdapter extends DisplayAdapter {
 
     private boolean mPendingStatusChangeBroadcast;
 
+    private static final String[] RECEIVER_PERMISSIONS_FOR_BROADCAST = {
+            android.Manifest.permission.ACCESS_FINE_LOCATION,
+    };
+
     // Called with SyncRoot lock held.
     public WifiDisplayAdapter(DisplayManagerService.SyncRoot syncRoot,
             Context context, Handler handler, Listener listener,
@@ -432,7 +436,8 @@ final class WifiDisplayAdapter extends DisplayAdapter {
         }
 
         // Send protected broadcast about wifi display status to registered receivers.
-        getContext().sendBroadcastAsUser(intent, UserHandle.ALL);
+        getContext().createContextAsUser(UserHandle.ALL, 0)
+                .sendBroadcastWithMultiplePermissions(intent, RECEIVER_PERMISSIONS_FOR_BROADCAST);
     }
 
     private final BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {