Hide current soft input when a background user gains window focus.

Bug: 7507226
Change-Id: If58f68469e21eaaba8536c4b54b3aa8cf8c08eb5

Author: satok16

services/java/com/android/server/InputMethodManagerService.java

@@ -1814,9 +1814,9 @@ boolean hideCurrentInputLocked(int flags, ResultReceiver resultReceiver) {
     public InputBindResult windowGainedFocus(IInputMethodClient client, IBinder windowToken,
             int controlFlags, int softInputMode, int windowFlags,
             EditorInfo attribute, IInputContext inputContext) {
-        if (!calledFromValidUser()) {
-            return null;
-        }
+        // Needs to check the validity before clearing calling identity
+        final boolean calledFromValidUser = calledFromValidUser();
+
         InputBindResult res = null;
         long ident = Binder.clearCallingIdentity();
         try {
@@ -1846,6 +1846,14 @@ public InputBindResult windowGainedFocus(IInputMethodClient client, IBinder wind
                 } catch (RemoteException e) {
                 }
 
+                if (!calledFromValidUser) {
+                    Slog.w(TAG, "A background user is requesting window. Hiding IME.");
+                    Slog.w(TAG, "If you want to interect with IME, you need "
+                            + "android.permission.INTERACT_ACROSS_USERS_FULL");
+                    hideCurrentInputLocked(0, null);
+                    return null;
+                }
+
                 if (mCurFocusedWindow == windowToken) {
                     Slog.w(TAG, "Window already focused, ignoring focus gain of: " + client
                             + " attribute=" + attribute + ", token = " + windowToken);