Add API support for multi-endpoint.

This CL includes changes required to support multi-endpoint (see the
design doc linked off the bug).

Main changes include:
- support for indicating if a call/connection is "external" to the device.
- support for indicating if an external call can be pulled from the
remote device to the local device.
- API used to initiate a pull of a call external to the current device to
the current device.
- Made the "connection event" API public (was previously @hide); this will
be used to support passing some error events involving pulling calls to
the incall ui.
- Added new InCallService metadata which will be used to determine if an
InCallService wants to be informed of external calls.
- New disconnect causes which will be used to expose the fact that a
multi-endpoint call was answered elsewhere and that a call ended because
it was pulled to another device.
- New call log call types to indicate if calls were answered elsewhere
or pulled to another device.

Bug: 27458894
Change-Id: I423f64ff965b5e50194635a51868c327782db2a1
diff --git a/telecomm/java/android/telecom/DisconnectCause.java b/telecomm/java/android/telecom/DisconnectCause.java
index 2eef7ee..cf73d4f 100644
--- a/telecomm/java/android/telecom/DisconnectCause.java
+++ b/telecomm/java/android/telecom/DisconnectCause.java
@@ -64,6 +64,17 @@
      */
     public static final int CONNECTION_MANAGER_NOT_SUPPORTED = 10;
 
+    /**
+     * Disconnected because the user did not locally answer the incoming call, but it was answered
+     * on another device where the call was ringing.
+     */
+    public static final int ANSWERED_ELSEWHERE = 11;
+
+    /**
+     * Disconnected because the call was pulled from the current device to another device.
+     */
+    public static final int CALL_PULLED = 12;
+
     private int mDisconnectCode;
     private CharSequence mDisconnectLabel;
     private CharSequence mDisconnectDescription;