Fixes regression (and crash) in instant. The crash would happen if

views/focus/focus_manager.h

Index: views/focus/focus_manager.h
diff --git a/views/focus/focus_manager.h b/views/focus/focus_manager.h
index f2bf0693855421785da0891cbe3761ed1c979efa..88f7a1c23209c6abf024b27e69e9083c36516527 100644
--- a/views/focus/focus_manager.h
+++ b/views/focus/focus_manager.h
@@ -225,6 +225,9 @@ class VIEWS_EXPORT FocusManager {
   // Clears the stored focused view.
   void ClearStoredFocusedView();
 
+  // Returns true if in the process of changing the focused view.
+  bool is_changing_focus() const { return is_changing_focus_; }
+
   // Register a keyboard accelerator for the specified target. If multiple
   // targets are registered for an accelerator, a target registered later has
   // higher priority.
@@ -313,6 +316,9 @@ class VIEWS_EXPORT FocusManager {
   // The list of registered FocusChange listeners.
   ObserverList<FocusChangeListener, true> focus_change_listeners_;
 
+  // See description above getter.
+  bool is_changing_focus_;
+
   DISALLOW_COPY_AND_ASSIGN(FocusManager);
 };