VoWifi notification for emergency calls

- Add new intent to send VOWIFI_ENABLED status

Bug: 179122732
Test: Manually verified by simulating

Change-Id: Iaf52a642a0435a070b8280b098e7929cddde55f6
Merged-In: Iaf52a642a0435a070b8280b098e7929cddde55f6
diff --git a/core/res/res/values/strings.xml b/core/res/res/values/strings.xml
index 96cd839..33554f7 100644
--- a/core/res/res/values/strings.xml
+++ b/core/res/res/values/strings.xml
@@ -234,9 +234,9 @@
     <!-- Displayed to tell the user that they should switch their network preference. -->
     <string name="NetworkPreferenceSwitchSummary">Try changing preferred network. Tap to change.</string>
     <!-- Displayed to tell the user that emergency calls might not be available. -->
-    <string name="EmergencyCallWarningTitle">Emergency calling unavailable</string>
+    <string name="EmergencyCallWarningTitle">Emergency calls may be unavailable</string>
     <!-- Displayed to tell the user that emergency calls might not be available. -->
-    <string name="EmergencyCallWarningSummary">Can\u2019t make emergency calls over Wi\u2011Fi</string>
+    <string name="EmergencyCallWarningSummary"><xliff:g id="spn" example="Operator">%s</xliff:g> doesn\'t support emergency calls over Wi-Fi. Tap for details.</string>
 
     <!-- Telephony notification channel name for a channel containing network alert notifications. -->
     <string name="notification_channel_network_alert">Alerts</string>
diff --git a/telephony/java/com/android/internal/telephony/TelephonyIntents.java b/telephony/java/com/android/internal/telephony/TelephonyIntents.java
index b905212..546d2ce 100644
--- a/telephony/java/com/android/internal/telephony/TelephonyIntents.java
+++ b/telephony/java/com/android/internal/telephony/TelephonyIntents.java
@@ -424,4 +424,24 @@
      */
     @Deprecated
     public static final String EXTRA_DEFAULT_NETWORK_AVAILABLE = "defaultNetworkAvailable";
+
+    /**
+     * <p>Broadcast sent to show Emergency notification due to Voice Over Wifi availability
+     *
+     * <p class="note">
+     * You can <em>not</em> receive this through components declared
+     * in manifests, only by explicitly registering for it with
+     * {@link android.content.Context#registerReceiver(android.content.BroadcastReceiver,
+     * android.content.IntentFilter) Context.registerReceiver()}.
+     *
+     * <p class="note">
+     * Requires no permission.
+     *
+     * <p class="note">This is a protected intent that can only be sent
+     * by the system.
+     *
+     * @hide
+     */
+    public static final String ACTION_VOWIFI_ENABLED
+            = "com.android.internal.telephony.ACTION_VOWIFI_ENABLED";
 }