Capture layer and children when calling takeSurfaceControlScreenshot

When calling UiAutomationConnection.takeSurfaceControlScreenshot, it
should capture the requested SurfaceControl and its children. The
current code only captures the children. Therefore, call setChildrenOnly
with false to ensure it captures the parent, as well.

Test: ASurfaceControlTest
Bug: 185390632
Change-Id: I62707f808934177c8db05485ac28559982b8c607

core/java/android/app/UiAutomationConnection.java

@@ -220,7 +220,9 @@ public final class UiAutomationConnection extends IUiAutomationConnection.Stub {
         final long identity = Binder.clearCallingIdentity();
         try {
             captureBuffer = SurfaceControl.captureLayers(
-                    new SurfaceControl.LayerCaptureArgs.Builder(surfaceControl).build());
+                    new SurfaceControl.LayerCaptureArgs.Builder(surfaceControl)
+                            .setChildrenOnly(false)
+                            .build());
         } finally {
             Binder.restoreCallingIdentity(identity);
         }