Make "source" a required argument of AppLaunchParams and fill in the argument in all call points.

chrome/browser/search/hotword_service.cc

Index: chrome/browser/search/hotword_service.cc
diff --git a/chrome/browser/search/hotword_service.cc b/chrome/browser/search/hotword_service.cc
index 64e7430a715569aa4a5ba14663db9f37f6223c5a..76b15165dedcd9a1f3d903c9ffe35a1035ee8133 100644
--- a/chrome/browser/search/hotword_service.cc
+++ b/chrome/browser/search/hotword_service.cc
@@ -21,6 +21,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search/hotword_audio_history_handler.h"
 #include "chrome/browser/search/hotword_service_factory.h"
+#include "chrome/browser/ui/extensions/app_launch_params.h"
 #include "chrome/browser/ui/extensions/application_launch.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
@@ -33,6 +34,7 @@
 #include "content/public/common/webplugininfo.h"
 #include "extensions/browser/extension_system.h"
 #include "extensions/browser/uninstall_reason.h"
+#include "extensions/common/constants.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/one_shot_event.h"
 #include "ui/base/l10n/l10n_util.h"
@@ -487,8 +489,9 @@ void HotwordService::LaunchHotwordAudioVerificationApp(
   if (!extension)
     return;
 
-  OpenApplication(AppLaunchParams(
-      profile_, extension, extensions::LAUNCH_CONTAINER_WINDOW, NEW_WINDOW));
+  OpenApplication(
+      AppLaunchParams(profile_, extension, extensions::LAUNCH_CONTAINER_WINDOW,
+                      NEW_WINDOW, extensions::SOURCE_CHROME_INTERNAL));
 }
 
 HotwordService::LaunchMode