Resolve cross-user image exploit for conference status hints

Ensure that status hint image icon is validated for cross-user exploits.
Currently, there is no check for this so a conference call can display
an image from another user, exposing a vulnerability.

Bug: 329058967
Test: Manual with POC
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:a8e2bf9c77cd94f683979c849015b78ef0537802)
Merged-In: Ib9d701398d25d021cdb9abacbaa5b175f62bee1d
Change-Id: Ib9d701398d25d021cdb9abacbaa5b175f62bee1d

src/com/android/server/telecom/ConnectionServiceWrapper.java

@@ -139,10 +139,17 @@ public void handleCreateConferenceComplete(String callId, ConnectionRequest requ
                 ParcelableConference conference, Session.Info sessionInfo) {
             Log.startSession(sessionInfo, LogUtils.Sessions.CSW_HANDLE_CREATE_CONNECTION_COMPLETE,
                     mPackageAbbreviation);
+            UserHandle callingUserHandle = Binder.getCallingUserHandle();
             long token = Binder.clearCallingIdentity();
             try {
                 synchronized (mLock) {
                     logIncoming("handleCreateConferenceComplete %s", callId);
+                    // Check status hints image for cross user access
+                    if (conference.getStatusHints() != null) {
+                        Icon icon = conference.getStatusHints().getIcon();
+                        conference.getStatusHints().setIcon(StatusHints.
+                                validateAccountIconUserBoundary(icon, callingUserHandle));
+                    }
                     Call call = mCallIdMapper.getCall(callId);
                     if (mScheduledFutureMap.containsKey(call)) {
                         ScheduledFuture<?> existingTimeout = mScheduledFutureMap.get(call);