Fix mismatchecd use of isEmpty in Sidecar

Replace use of isEmpty with check for zero Rect.

Test: n/a
Bug: 160827187
Change-Id: I22c041e095fd9b28c3b526f78e2adecd2ea4b88e

libs/WindowManager/Jetpack/src/androidx/window/sidecar/SettingsSidecarImpl.java

@@ -192,7 +192,7 @@ class SettingsSidecarImpl extends StubSidecar {
                 Rect featureRect = new Rect(left, top, right, bottom);
                 rotateRectToDisplayRotation(featureRect, displayId);
                 transformToWindowSpaceRect(featureRect, windowToken);
-                if (!featureRect.isEmpty()) {
+                if (isNotZero(featureRect)) {
                     SidecarDisplayFeature feature = new SidecarDisplayFeature();
                     feature.setRect(featureRect);
                     feature.setType(type);
@@ -207,6 +207,10 @@ class SettingsSidecarImpl extends StubSidecar {
         return features;
     }
 
+    private static boolean isNotZero(Rect rect) {
+        return rect.height() > 0 || rect.width() > 0;
+    }
+
     @Override
     protected void onListenersChanged() {
         if (mSettingsObserver == null) {