Merge "Prevent IMEs from switching to another IME that isn't enabled" into tm-qpr-dev am: 1b2695237b

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21342766

Change-Id: Ief5e884a8ebe39cd20cfda8e938e5263ade2888e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

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

@@ -4831,6 +4831,13 @@ public final class InputMethodManagerService extends IInputMethodManager.Stub
             Slog.w(TAG, "Ignoring setInputMethod of uid " + Binder.getCallingUid()
                     + " token: " + token);
             return;
+        } else {
+            // Called with current IME's token.
+            if (mMethodMap.get(id) != null
+                    && mSettings.getEnabledInputMethodListWithFilterLocked(
+                            (info) -> info.getId().equals(id)).isEmpty()) {
+                throw new IllegalStateException("Requested IME is not enabled: " + id);
+            }
         }
 
         final long ident = Binder.clearCallingIdentity();