[ios] Adds support for Find in Page to the new architecture.

ios/clean/chrome/browser/ui/tab/tab_container_view_controller.h

Index: ios/clean/chrome/browser/ui/tab/tab_container_view_controller.h
diff --git a/ios/clean/chrome/browser/ui/tab/tab_container_view_controller.h b/ios/clean/chrome/browser/ui/tab/tab_container_view_controller.h
index f5dd0bd52bd7ed3379ce758edfe05f7452734b5b..43e3f684867882ef5b49f45b2042b8edcd26c781 100644
--- a/ios/clean/chrome/browser/ui/tab/tab_container_view_controller.h
+++ b/ios/clean/chrome/browser/ui/tab/tab_container_view_controller.h
@@ -35,6 +35,11 @@
 // width of the tab.
 @property(nonatomic, strong) UIViewController* tabStripViewController;
 
+// View controller showing the find bar.  The location of this controller's view
+// is determined by size class and device type.  May be nil if the find bar is
+// currently closed.
+@property(nonatomic, strong) UIViewController* findBarViewController;
+
 @end
 
 // Tab container which positions the toolbar at the top.