Prevent duplicate concurrent installs of the same extension

chrome/browser/extensions/webstore_standalone_installer.h

Index: chrome/browser/extensions/webstore_standalone_installer.h
diff --git a/chrome/browser/extensions/webstore_standalone_installer.h b/chrome/browser/extensions/webstore_standalone_installer.h
index 7df7bff9f6322f76e83ccbd435849dc9c669a523..36ddf0807f6b89247ee5741856127cd2ed83c08a 100644
--- a/chrome/browser/extensions/webstore_standalone_installer.h
+++ b/chrome/browser/extensions/webstore_standalone_installer.h
@@ -10,6 +10,7 @@
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "chrome/browser/extensions/active_install_data.h"
 #include "chrome/browser/extensions/extension_install_prompt.h"
 #include "chrome/browser/extensions/webstore_data_fetcher_delegate.h"
 #include "chrome/browser/extensions/webstore_install_helper.h"
@@ -64,6 +65,11 @@ class WebstoreStandaloneInstaller
   // Called when the install should be aborted. The callback is cleared.
   void AbortInstall();
 
+  // Checks InstallTracker and returns true if the same extension is not
+  // currently being installed. Registers this install with the InstallTracker.
+  bool EnsureUniqueInstall(webstore_install::Result* reason,
+                           std::string* error);
+
   // Called when the install is complete.
   virtual void CompleteInstall(webstore_install::Result result,
                                const std::string& error);
@@ -78,6 +84,10 @@ class WebstoreStandaloneInstaller
 
   // Template Method's hooks to be implemented by subclasses.
 
+  // Called when this install is about to be registered with the InstallTracker.
+  // Allows subclasses to set properties of the install data.
+  virtual void InitInstallData(ActiveInstallData* install_data) const;
+
   // Called at certain check points of the workflow to decide whether it makes
   // sense to proceed with installation. A requestor can be a website that
   // initiated an inline installation, or a command line option.
@@ -228,6 +238,9 @@ class WebstoreStandaloneInstaller
   scoped_ptr<base::DictionaryValue> manifest_;
   SkBitmap icon_;
 
+  // Active install registered with the InstallTracker.
+  scoped_ptr<ScopedActiveInstall> scoped_active_install_;
+
   // Created by ShowInstallUI() when a prompt is shown (if
   // the implementor returns a non-NULL in CreateInstallPrompt()).
   scoped_refptr<Extension> localized_extension_for_display_;