Remove handover token.

Removing handover token and cleaning up the references to it in the docs.
This was supposed to go into the original CL but it looks like the upload
failed.

Test: Manual
Bug: 37102939
Change-Id: I98f392119258d059669ca68b50184b8bdadbcf0f
diff --git a/telecomm/java/android/telecom/TelecomManager.java b/telecomm/java/android/telecom/TelecomManager.java
index 8f8ba6d..47f3fbe 100644
--- a/telecomm/java/android/telecom/TelecomManager.java
+++ b/telecomm/java/android/telecom/TelecomManager.java
@@ -342,24 +342,12 @@
      * to indicate to Telecom that the purpose of adding a new incoming call is to handover an
      * existing call from the user's device to a different {@link PhoneAccount}.
      * <p>
-     * The caller must also include {@link #EXTRA_HANDOVER_TOKEN} to specify which existing call is
-     * to be handed over.
+     * The phone number of the call used by Telecom to determine which call should be handed over.
      * @hide
      */
     public static final String EXTRA_IS_HANDOVER = "android.telecom.extra.IS_HANDOVER";
 
     /**
-     * String extra which identifies the existing call on the current device which will be handed
-     * over.  This is a Telecom-specific opaque token; the caller should not make any assumptions
-     * about its meaning or content.
-     * <p>
-     * Used alongside {@link #EXTRA_IS_HANDOVER} when calling
-     * {@link #addNewIncomingCall(PhoneAccountHandle, Bundle)}.
-     * @hide
-     */
-    public static final String EXTRA_HANDOVER_TOKEN = "android.telecom.extra.HANDOVER_TOKEN";
-
-    /**
      * A boolean extra, which when set on the {@link Intent#ACTION_CALL} intent or on the bundle
      * passed into {@link #placeCall(Uri, Bundle)}, indicates that the call should be initiated with
      * an RTT session open. See {@link android.telecom.Call.RttCall} for more information on RTT.