Fixed the issue shows keyword hint when omnibox loses its focus.

chrome/browser/ui/omnibox/chrome_omnibox_edit_controller.h

Index: chrome/browser/ui/omnibox/chrome_omnibox_edit_controller.h
diff --git a/chrome/browser/ui/omnibox/chrome_omnibox_edit_controller.h b/chrome/browser/ui/omnibox/chrome_omnibox_edit_controller.h
index a9c0d0f7f3122ee4e8a0182a81be1781ec3ecc8d..fe776db99220758a46707706db6fa12770907d68 100644
--- a/chrome/browser/ui/omnibox/chrome_omnibox_edit_controller.h
+++ b/chrome/browser/ui/omnibox/chrome_omnibox_edit_controller.h
@@ -7,6 +7,7 @@
 
 #include "base/macros.h"
 #include "components/omnibox/browser/omnibox_edit_controller.h"
+#include "components/omnibox/common/omnibox_focus_state.h"
 
 class CommandUpdater;
 
@@ -24,6 +25,9 @@ class ChromeOmniboxEditController : public OmniboxEditController {
   // tab state.
   virtual void UpdateWithoutTabRestore() = 0;
 
+  // Called when omnibox focus was changed.
+  virtual void OnFocusChanged(OmniboxFocusState state) = 0;
+
   CommandUpdater* command_updater() { return command_updater_; }
   const CommandUpdater* command_updater() const { return command_updater_; }