[scroll-animations-1] Add privacy and security considerations sections.

Author: flackr

scroll-animations-1/Overview.bs

@@ -838,6 +838,14 @@ spec: cssom-view-1; type: dfn;
 	and the state of a scroll-driven animation
 	may be inconsistent in the composited frame.
 
+# Privacy Considerations
+
+  There are no known privacy impacts of the features in this specification.
+
+# Security Considerations
+
+  There are no known security impacts of the features in this specification.
+
 # Appendix A: Named Timeline Ranges # {#timeline-ranges}
 
 	ISSUE: This section should move to CSS-ANIMATIONS-2 and WEB-ANIMATIONS-2.