Prevent duplicate concurrent installs of the same extension

chrome/browser/ui/app_list/search/webstore/webstore_result.cc

Index: chrome/browser/ui/app_list/search/webstore/webstore_result.cc
diff --git a/chrome/browser/ui/app_list/search/webstore/webstore_result.cc b/chrome/browser/ui/app_list/search/webstore/webstore_result.cc
index 50dea34a92b0e08943f2aa622feaf3130c7ade8b..accad910caba51f40f197a0b906e0a66ca81e368 100644
--- a/chrome/browser/ui/app_list/search/webstore/webstore_result.cc
+++ b/chrome/browser/ui/app_list/search/webstore/webstore_result.cc
@@ -74,7 +74,8 @@ WebstoreResult::WebstoreResult(Profile* profile,
       icon_url_(icon_url),
       weak_factory_(this),
       controller_(controller),
-      install_tracker_(NULL),
+      install_tracker_(
+          extensions::InstallTrackerFactory::GetForProfile(profile)),
       extension_registry_(NULL) {
   set_id(extensions::Extension::GetBaseURLFromExtensionId(app_id_).spec());
   set_relevance(0.0);  // What is the right value to use?
@@ -82,6 +83,7 @@ WebstoreResult::WebstoreResult(Profile* profile,
   set_title(base::UTF8ToUTF16(localized_name_));
   SetDefaultDetails();
 
+  SetInitialState();
   UpdateActions();
 
   icon_ = gfx::ImageSkia(
@@ -124,6 +126,15 @@ scoped_ptr<ChromeSearchResult> WebstoreResult::Duplicate() {
       profile_, app_id_, localized_name_, icon_url_, controller_)).Pass();
 }
 
+void WebstoreResult::SetInitialState() {
+  const extensions::InstallTracker::InstallProgressData* install_data =
+      install_tracker_->GetActiveInstall(app_id_);
+  if (install_data) {
+    SetPercentDownloaded(install_data->percent_downloaded);
+    SetIsInstalling(true);
+  }
+}
+
 void WebstoreResult::UpdateActions() {
   Actions actions;
 
@@ -219,9 +230,8 @@ void WebstoreResult::LaunchCallback(extensions::webstore_install::Result result,
 }
 
 void WebstoreResult::StartObserving() {
-  DCHECK(!install_tracker_ && !extension_registry_);
+  DCHECK(!extension_registry_);
 
-  install_tracker_ = extensions::InstallTrackerFactory::GetForProfile(profile_);
   install_tracker_->AddObserver(this);
 
   extension_registry_ = extensions::ExtensionRegistry::Get(profile_);
@@ -258,10 +268,10 @@ void WebstoreResult::OnExtensionWillBeInstalled(
     return;
 
   SetIsInstalling(false);
+  UpdateActions();
 
   if (extensions::util::IsExtensionInstalledPermanently(extension->id(),
                                                         profile_)) {
-    UpdateActions();
     NotifyItemInstalled();
   }
 }