Add passive and FOV-locked properties to UI elements.

chrome/browser/android/vr_shell/ui_elements.h

Index: chrome/browser/android/vr_shell/ui_elements.h
diff --git a/chrome/browser/android/vr_shell/ui_elements.h b/chrome/browser/android/vr_shell/ui_elements.h
index 7316eaa34cd2d97c01702426e30582d14c6de857..fda2a2fa2b819d6ca2f106165eb13e621bfb77fe 100644
--- a/chrome/browser/android/vr_shell/ui_elements.h
+++ b/chrome/browser/android/vr_shell/ui_elements.h
@@ -70,9 +70,16 @@ struct ContentRectangle : public WorldRectangle {
   // are applied relative to the parent, rather than absolutely.
   int parent_id = -1;
 
-  // If true, this object will be visible and accept input.
+  // If true, this object will be visible.
   bool visible = true;
 
+  // If false, the reticle will not hit the element, even if visible.
+  bool hit_testable = true;
+
+  // If true, transformations will be applied relative to the field of view,
+  // rather than the world.
+  bool lock_to_fov = false;
+
   // Specifies the region (in pixels) of a texture to render.
   Recti copy_rect = {0, 0, 0, 0};