Open the launcher when hotword is triggered in always-on mode.

chrome/browser/search/hotword_service.h

Index: chrome/browser/search/hotword_service.h
diff --git a/chrome/browser/search/hotword_service.h b/chrome/browser/search/hotword_service.h
index 600883aadfafd0fa6d2fb8070edd5247b68693b4..640c088f687d68d0c73ef93237fe7e95574273c8 100644
--- a/chrome/browser/search/hotword_service.h
+++ b/chrome/browser/search/hotword_service.h
@@ -72,6 +72,9 @@ class HotwordService : public content::NotificationObserver,
   // is opted in, false otherwise..
   bool IsOptedIntoAudioLogging();
 
+  // Returns whether always-on hotwording is enabled.
+  bool IsAlwaysOnEnabled();
+
   // Control the state of the hotword extension.
   void EnableHotwordExtension(ExtensionService* extension_service);
   void DisableHotwordExtension(ExtensionService* extension_service);