Only register conditions receiver when needed.

1. Update the dnd receiver to listen when dashboard summary running.
- remove the dnd receiver from Android manifest, and create it inside
the dnd condition.
- add lifecycle implementation to condition manager, so that the dnd
condition can know when to register and unregister the receiver.
- remove getReceiverClass() from dnd condition so that its receiver will
not be disabled by the default condition handling when condition is
silenced.

2. Remove all other conditions receiver from Android manifest.
- the broadcast receivers for HotspotCondition, AirplaneModeCondition,
CellularDataCondition from the manifest and create them inside the
condition classes.
- update Condition.onSilenceChanged() to register/unregister the
receivers instead of enable/disable the receiver class.

Change-Id: Iea6288382680df2b02884d1934b8db85daae404c
Fix: 35968517
Test: make RunSettingsRoboTests

src/com/android/settings/dashboard/conditional/HotspotCondition.java

@@ -18,6 +18,7 @@ package com.android.settings.dashboard.conditional;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
+import android.content.IntentFilter;
 import android.graphics.drawable.Icon;
 import android.net.ConnectivityManager;
 import android.net.wifi.WifiConfiguration;
@@ -31,15 +32,19 @@ import com.android.settings.TetherSettings;
 import com.android.settings.Utils;
 import com.android.settingslib.RestrictedLockUtils;
 import com.android.settingslib.RestrictedLockUtils.EnforcedAdmin;
-import com.android.settingslib.TetherUtil;
 
 public class HotspotCondition extends Condition {
 
     private final WifiManager mWifiManager;
+    private final Receiver mReceiver;
+
+    private static final IntentFilter WIFI_AP_STATE_FILTER =
+        new IntentFilter(WifiManager.WIFI_AP_STATE_CHANGED_ACTION);
 
     public HotspotCondition(ConditionManager manager) {
         super(manager);
         mWifiManager = mManager.getContext().getSystemService(WifiManager.class);
+        mReceiver = new Receiver();
     }
 
     @Override
@@ -49,8 +54,13 @@ public class HotspotCondition extends Condition {
     }
 
     @Override
-    protected Class<?> getReceiverClass() {
-        return Receiver.class;
+    protected BroadcastReceiver getReceiver() {
+        return mReceiver;
+    }
+
+    @Override
+    protected IntentFilter getIntentFilter() {
+        return WIFI_AP_STATE_FILTER;
     }
 
     @Override