[Extensions] Update Error Console UI

chrome/browser/extensions/error_console/error_console.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_ERROR_CONSOLE_ERROR_CONSOLE_H_
 #define CHROME_BROWSER_EXTENSIONS_ERROR_CONSOLE_ERROR_CONSOLE_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "base/prefs/pref_change_registrar.h"
@@ skipping 24 matching lines @@
 // runtime Javascript errors. If FeatureSwitch::error_console() is enabled these
 // errors can be viewed at chrome://extensions in developer mode.
 // This class is owned by ExtensionSystem, making it, in effect, a
 // BrowserContext-keyed service.
 class ErrorConsole : public content::NotificationObserver,
                      public ExtensionRegistryObserver {
  public:
   class Observer {
    public:
     // Sent when a new error is reported to the error console.
-    virtual void OnErrorAdded(const ExtensionError* error) = 0;
+    virtual void OnErrorAdded(const ExtensionError* error);
+
+    // Sent when errors are removed from the error console. |extension_ids| is
+    // the set of ids that were affected.
+    // Note: This is not sent when an extension is uninstalled, or when a
+    // profile is destroyed.
+    virtual void OnErrorsRemoved(const std::set<std::string>& extension_ids);
 
     // Sent upon destruction to allow any observers to invalidate any references
     // they have to the error console.
     virtual void OnErrorConsoleDestroyed();
   };
 
   explicit ErrorConsole(Profile* profile);
   ~ErrorConsole() override;
 
   // Convenience method to return the ErrorConsole for a given |context|.
@@ skipping 131 matching lines @@
 
   ScopedObserver<ExtensionRegistry, ExtensionRegistryObserver>
       registry_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(ErrorConsole);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_ERROR_CONSOLE_ERROR_CONSOLE_H_