Add private_space_floating_mask_view flag.

bug: 339850589
Test: In follow up CL
Flag: ACONFIG com.android.launcher3.private_space_floating_mask_view DEVELOPMENT
Change-Id: Idc03b9d3439046e6a1397599b33c7af9f53b1333
diff --git a/aconfig/launcher_search.aconfig b/aconfig/launcher_search.aconfig
index 31d8d34..b243922 100644
--- a/aconfig/launcher_search.aconfig
+++ b/aconfig/launcher_search.aconfig
@@ -42,3 +42,11 @@
     description: "This flag disables drag and drop for Private Space Items."
     bug: "289223923"
 }
+
+
+flag {
+    name: "private_space_floating_mask_view"
+    namespace: "launcher_search"
+    description: "This flag enables the floating mask view as part of the Private Space animation. "
+    bug: "339850589"
+}