Hide multi-endpoint APIs.

Per feature council decision, the multi-endpoint APIs will be @hide for
the N release.

Bug: 28196918
Change-Id: Ia80b089bc754ce87ca208382eb79442b5265844d
diff --git a/telecomm/java/android/telecom/Call.java b/telecomm/java/android/telecom/Call.java
index b4c6e6a..39a1207 100644
--- a/telecomm/java/android/telecom/Call.java
+++ b/telecomm/java/android/telecom/Call.java
@@ -104,6 +104,7 @@
      * An {@link InCallService} will only see this state if it has the
      * {@link TelecomManager#METADATA_INCLUDE_EXTERNAL_CALLS} metadata set to {@code true} in its
      * manifest.
+     * @hide
      */
     public static final int STATE_PULLING_CALL = 11;
 
@@ -251,6 +252,7 @@
          * <p>
          * See {@link Connection#CAPABILITY_CAN_PULL_CALL} and
          * {@link Connection#PROPERTY_IS_EXTERNAL_CALL}.
+         * @hide
          */
         public static final int CAPABILITY_CAN_PULL_CALL = 0x00800000;
 
@@ -303,6 +305,7 @@
          * in its manifest.
          * <p>
          * See {@link Connection#PROPERTY_IS_EXTERNAL_CALL}.
+         * @hide
          */
         public static final int PROPERTY_IS_EXTERNAL_CALL = 0x00000040;
 
@@ -783,6 +786,7 @@
          * @param call The {@code Call} receiving the event.
          * @param event The event.
          * @param extras Extras associated with the connection event.
+         * @hide
          */
         public void onConnectionEvent(Call call, String event, Bundle extras) {}
     }
@@ -961,6 +965,7 @@
      * An {@link InCallService} will only see calls which support this method if it has the
      * {@link TelecomManager#METADATA_INCLUDE_EXTERNAL_CALLS} metadata set to {@code true}
      * in its manifest.
+     * @hide
      */
     public void pullExternalCall() {
         // If this isn't an external call, ignore the request.
@@ -983,6 +988,7 @@
      *
      * @param event The connection event.
      * @param extras Bundle containing extra information associated with the event.
+     * @hide
      */
     public void sendCallEvent(String event, Bundle extras) {
         mInCallAdapter.sendCallEvent(mTelecomCallId, event, extras);
@@ -996,6 +1002,7 @@
      * extras.  Keys should be fully qualified (e.g., com.example.MY_EXTRA) to avoid conflicts.
      *
      * @param extras The extras to add.
+     * @hide
      */
     public final void putExtras(Bundle extras) {
         if (extras == null) {
@@ -1058,6 +1065,7 @@
      * Removes extras from this {@code Connection}.
      *
      * @param keys The keys of the extras to remove.
+     * @hide
      */
     public final void removeExtras(List<String> keys) {
         if (mExtras != null) {