[win] Add a progress bar in the app launcher for app installs.

chrome/browser/ui/app_list/app_list_view_delegate.cc

Index: chrome/browser/ui/app_list/app_list_view_delegate.cc
diff --git a/chrome/browser/ui/app_list/app_list_view_delegate.cc b/chrome/browser/ui/app_list/app_list_view_delegate.cc
index c0a79551efd7b5aad0a0857388888fb7327143c9..15d294e0257f55d01df201744a685c0446fa329e 100644
--- a/chrome/browser/ui/app_list/app_list_view_delegate.cc
+++ b/chrome/browser/ui/app_list/app_list_view_delegate.cc
@@ -63,6 +63,12 @@ void AppListViewDelegate::OnBeginExtensionInstall(
                                          installing_icon);
 }
 
+void AppListViewDelegate::OnDownloadProgress(
+    const std::string& extension_id,
+    int percent_downloaded) {
+  apps_builder_->OnDownloadProgress(extension_id, percent_downloaded);
+}
+
 void AppListViewDelegate::ActivateAppListItem(
     app_list::AppListItemModel* item,
     int event_flags) {