WMS retrieves uid for the package based on the linux user

Without this, checking if the caller is the recents component always
fails on the secondary user.

Bug: 254937640
Test: atest WmTests:WindowManagerServiceTests
Change-Id: Iac9fea3935c3aadf29a21d8af715df845e8ea43c

core/java/android/view/IWindowManager.aidl

@@ -738,9 +738,8 @@ interface IWindowManager
      * If invoked through a package other than a launcher app, returns an empty list.
      *
      * @param displayId the id of the logical display
-     * @param packageName the name of the calling package
      */
-    List<DisplayInfo> getPossibleDisplayInfo(int displayId, String packageName);
+    List<DisplayInfo> getPossibleDisplayInfo(int displayId);
 
     /**
      * Called to show global actions.

core/java/android/view/WindowManagerImpl.java

@@ -366,7 +366,7 @@ public final class WindowManagerImpl implements WindowManager {
         List<DisplayInfo> possibleDisplayInfos;
         try {
             possibleDisplayInfos = WindowManagerGlobal.getWindowManagerService()
-                    .getPossibleDisplayInfo(displayId, mContext.getPackageName());
+                    .getPossibleDisplayInfo(displayId);
         } catch (RemoteException e) {
             throw e.rethrowFromSystemServer();
         }

services/core/java/com/android/server/wm/WindowManagerService.java

@@ -8940,14 +8940,14 @@ public class WindowManagerService extends IWindowManager.Stub
     }
 
     @Override
-    public List<DisplayInfo> getPossibleDisplayInfo(int displayId, String packageName) {
+    public List<DisplayInfo> getPossibleDisplayInfo(int displayId) {
         final int callingUid = Binder.getCallingUid();
         final long origId = Binder.clearCallingIdentity();
         try {
             synchronized (mGlobalLock) {
-                if (packageName == null || !isRecentsComponent(packageName, callingUid)) {
+                if (!mAtmService.isCallerRecents(callingUid)) {
-                    Slog.e(TAG, "Unable to verify uid for package " + packageName
+                    Slog.e(TAG, "Unable to verify uid for getPossibleDisplayInfo"
-                            + " for getPossibleMaximumWindowMetrics");
+                            + " on uid " + callingUid);
                     return new ArrayList<>();
                 }
 
@@ -8965,31 +8965,6 @@ public class WindowManagerService extends IWindowManager.Stub
         return mPossibleDisplayInfoMapper.getPossibleDisplayInfos(displayId);
     }
 
-    /**
-     * Returns {@code true} when the calling package is the recents component.
-     */
-    boolean isRecentsComponent(@NonNull String callingPackageName, int callingUid) {
-        String recentsPackage;
-        try {
-            String recentsComponent = mContext.getResources().getString(
-                    R.string.config_recentsComponentName);
-            if (recentsComponent == null) {
-                return false;
-            }
-            recentsPackage = ComponentName.unflattenFromString(recentsComponent).getPackageName();
-        } catch (Resources.NotFoundException e) {
-            Slog.e(TAG, "Unable to verify if recents component", e);
-            return false;
-        }
-        try {
-            return callingUid == mContext.getPackageManager().getPackageUid(callingPackageName, 0)
-                    && callingPackageName.equals(recentsPackage);
-        } catch (PackageManager.NameNotFoundException e) {
-            Slog.e(TAG, "Unable to verify if recents component", e);
-            return false;
-        }
-    }
-
     void grantEmbeddedWindowFocus(Session session, IBinder focusToken, boolean grantFocus) {
         synchronized (mGlobalLock) {
             final EmbeddedWindowController.EmbeddedWindow embeddedWindow =