Route UI thread lifecycle through platform services

src/platform_legacy/legacy_platform_services.cpp

@@ -6,6 +6,8 @@
 
 #ifdef __ANDROID__
 void displayKeyboard(bool pShow);
+void android_attach_jni();
+void android_detach_jni();
 void android_pick_file(std::function<void(std::string)> callback);
 void android_pick_file_save(std::function<void(std::string)> callback);
 std::string android_get_clipboard();
@@ -88,6 +90,20 @@ public:
 #endif
     }
 
+    void attach_ui_thread() override
+    {
+#ifdef __ANDROID__
+        android_attach_jni();
+#endif
+    }
+
+    void detach_ui_thread() override
+    {
+#ifdef __ANDROID__
+        android_detach_jni();
+#endif
+    }
+
     void update_platform_frame(float delta_time_seconds) override
     {
         (void)delta_time_seconds;