Fix bug where we were not displaying icons in the management

chrome/browser/extensions/extensions_ui.h

Index: chrome/browser/extensions/extensions_ui.h
diff --git a/chrome/browser/extensions/extensions_ui.h b/chrome/browser/extensions/extensions_ui.h
index 37e73b62ed1e574ae3a139eafef4fc07a37dd489..b2b82c2211aa4cb1fb58c0c6d802713e2aca0c07 100644
--- a/chrome/browser/extensions/extensions_ui.h
+++ b/chrome/browser/extensions/extensions_ui.h
@@ -12,6 +12,7 @@
 #include "chrome/browser/dom_ui/dom_ui.h"
 #include "chrome/browser/extensions/pack_extension_job.h"
 #include "chrome/browser/shell_dialogs.h"
+#include "chrome/common/extensions/extension_resource.h"
 #include "chrome/common/notification_observer.h"
 #include "chrome/common/notification_registrar.h"
 #include "googleurl/src/gurl.h"
@@ -57,6 +58,41 @@ class ExtensionsDOMHandler
       public PackExtensionJob::Client,
       public SelectFileDialog::Listener {
  public:
+
+  // Helper class that loads the icons for the extensions in the management UI.
+  // We do this with native code instead of just using chrome-extension:// URLs
+  // for two reasons:
+  //
+  // 1. We need to support the disabled extensions, too, and using URLs won't
+  //    work for them.
+  // 2. We want to desaturate the icons of the disabled extensions to make them
+  //    look more disabled.
+  class IconLoader : public base::RefCountedThreadSafe<IconLoader> {
+   public:
+    IconLoader(ExtensionsDOMHandler* handler);
+
+    // Load |icons|. Will call handler->OnIconsLoaded when complete. IconLoader
+    // takes ownership of both arguments.
+    void LoadIcons(std::vector<ExtensionResource>* icons,
+                   DictionaryValue* json);
+
+    // Cancel the load. IconLoader won't try to call back to the handler after
+    // this.
+    void Cancel();
+
+   private:
+    // Load the icons and call ReportResultOnUIThread when done. This method
+    // takes ownership of both arguments.
+    void LoadIconsOnFileThread(std::vector<ExtensionResource>* icons,
+                               DictionaryValue* json);
+
+    // Report back to the handler. This method takes ownership of |json|.
+    void ReportResultOnUIThread(DictionaryValue* json);
+
+    // The handler we will report back to.
+    ExtensionsDOMHandler* handler_;
+  };
+
   explicit ExtensionsDOMHandler(ExtensionsService* extension_service);
   virtual ~ExtensionsDOMHandler();
 
@@ -135,6 +171,21 @@ class ExtensionsDOMHandler
   std::vector<ExtensionPage> GetActivePagesForExtension(
       const std::string& extension_id);
 
+  // Returns the best icon to display in the UI for an extension, or NULL if no
+  // good icon exists.
+  ExtensionResource PickExtensionIcon(Extension* extension);
+
+  // Loads the extension resources into the json data, then calls OnIconsLoaded.
+  // Takes ownership of |icons|.
+  // Called on the file thread.
+  void LoadExtensionIcons(std::vector<ExtensionResource>* icons,
+                          DictionaryValue* json_data);
+
+  // Tells the HTML about |json_data|.
+  // Takes ownership of |json_data|.
+  // Called on the UI thread.
+  void OnIconsLoaded(DictionaryValue* json_data);
+
   // Our model.
   scoped_refptr<ExtensionsService> extensions_service_;
 
@@ -144,6 +195,9 @@ class ExtensionsDOMHandler
   // Used to package the extension.
   scoped_refptr<PackExtensionJob> pack_job_;
 
+  // Used to load icons.

[Finnur, 2009/11/05 03:55:08]

nit: This comment is a bit scarce. Can you add: "asynchronously on the File
thread"?

+  scoped_refptr<IconLoader> icon_loader_;
+
   // We monitor changes to the extension system so that we can reload when
   // necessary.
   NotificationRegistrar registrar_;