sepolicy: rename use_smart_90_for_video -> use_content_detection_for_refresh_rate

Add a new entry for use_content_detection_for_refresh_rate that will
eventually replace the deprecated use_smart_90_for_video

Change-Id: Iffe83fe0c7620f661228452495a02922f9662406
Test: play video and observe refresh rate
diff --git a/public/property_contexts b/public/property_contexts
index 5e419ee..bdc862d 100644
--- a/public/property_contexts
+++ b/public/property_contexts
@@ -438,6 +438,7 @@
 ro.surface_flinger.set_display_power_timer_ms u:object_r:exported_default_prop:s0 exact int
 ro.surface_flinger.support_kernel_idle_timer u:object_r:exported_default_prop:s0 exact bool
 ro.surface_flinger.use_smart_90_for_video u:object_r:exported_default_prop:s0 exact bool
+ro.surface_flinger.use_content_detection_for_refresh_rate u:object_r:exported_default_prop:s0 exact bool
 ro.surface_flinger.color_space_agnostic_dataspace u:object_r:exported_default_prop:s0 exact int
 ro.surface_flinger.refresh_rate_switching u:object_r:exported_default_prop:s0 exact bool