Add Telecom notification channels.

Test: Manual
Bug: 36866129
Change-Id: I49194128b4f526205055137d4ebaa8b282baa90f
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 1cca867..2363a1d 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -247,4 +247,9 @@
          phone call in a third-party app.  Unlike cant_call_due_to_ongoing_call, this is used when
          the name of the other app is not known. [CHAR LIMIT=none] -->
     <string name="cant_call_due_to_ongoing_unknown_call">Call cannot be placed due to a call in another app.</string>
+
+    <!-- Notification channel name for a channel containing incoming call notifications. -->
+    <string name="notification_channel_incoming_call">Incoming calls</string>
+    <!-- Notification channel name for a channel containing missed call notifications. -->
+    <string name="notification_channel_missed_call">Missed calls</string>
 </resources>