Initial screenshot tests for bubble bar view

Flag: com.android.wm.shell.enable_bubble_bar
Bug: 355454021
Test: atest BubbleBarViewScreenshotTests
Change-Id: Id74c78d99a8b4528bb473c5a751edb19bda34007
diff --git a/quickstep/Android.bp b/quickstep/Android.bp
index 4c724dc..2ef9f82 100644
--- a/quickstep/Android.bp
+++ b/quickstep/Android.bp
@@ -64,3 +64,11 @@
         "tests/multivalentScreenshotTests/src/**/*.kt",
     ],
 }
+
+filegroup {
+    name: "launcher3-quickstep-testing",
+    path: "testing",
+    srcs: [
+        "testing/**/*.kt",
+    ],
+}