Block activity launching if DWPC does not allow

Prvent an activity from launching and return START_CANCELED if target
display's DWPC does not allow it.

Bug: 205811272
Test: atest ActivityBlockingTest ActivityStarterTests
Change-Id: I8b6bbc5713da035bd7320c507ba4f3f49bda8423

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

@@ -135,6 +135,7 @@ import com.android.server.wm.LaunchParamsController.LaunchParams;
 
 import java.io.PrintWriter;
 import java.text.DateFormat;
+import java.util.ArrayList;
 import java.util.Date;
 
 /**
@@ -2009,6 +2010,27 @@ class ActivityStarter {
             return START_PERMISSION_DENIED;
         }
 
+        // Do not start the activity if target display's DWPC does not allow it.
+        // We can't return fatal error code here because it will crash the caller of
+        // startActivity() if they don't catch the exception. We don't expect 3P apps to make
+        // changes.
+        if (mPreferredTaskDisplayArea != null) {
+            final DisplayContent displayContent = mRootWindowContainer.getDisplayContentOrCreate(
+                    mPreferredTaskDisplayArea.getDisplayId());
+            if (displayContent != null && displayContent.mDwpcHelper.hasController()) {
+                final ArrayList<ActivityInfo> activities = new ArrayList<>();
+                activities.add(r.info);
+                final int targetWindowingMode = (targetTask != null)
+                        ? targetTask.getWindowingMode() : displayContent.getWindowingMode();
+                if (!displayContent.mDwpcHelper
+                        .canContainActivities(activities, targetWindowingMode)) {
+                    Slog.w(TAG, "Abort to launch " + r.info.getComponentName()
+                            + " on display area " + mPreferredTaskDisplayArea);
+                    return START_ABORTED;
+                }
+            }
+        }
+
         return START_SUCCESS;
     }