Update the EphemeralAppLauncher for use by the webstorePrivate API

chrome/browser/apps/ephemeral_app_throttle.cc

Index: chrome/browser/apps/ephemeral_app_throttle.cc
diff --git a/chrome/browser/apps/ephemeral_app_throttle.cc b/chrome/browser/apps/ephemeral_app_throttle.cc
index be398cb5dac350041c4dc579bbb03160c264dd00..d4b04070ae1e34379846ebd7456c1984d48a4b9e 100644
--- a/chrome/browser/apps/ephemeral_app_throttle.cc
+++ b/chrome/browser/apps/ephemeral_app_throttle.cc
@@ -52,7 +52,8 @@ bool LaunchEphemeralApp(
   // The EphemeralAppLauncher will handle launching of an existing app or
   // installing and launching a new ephemeral app.
   scoped_refptr<EphemeralAppLauncher> installer =
-      EphemeralAppLauncher::CreateForLink(app_id, source);
+      EphemeralAppLauncher::CreateForWebContents(
+          app_id, source, EphemeralAppLauncher::LaunchCallback());
   installer->Start();
   return true;
 }