Observe OnExtensionLoaded to trigger update of chrome.commands keybindings for component extensions.

chrome/browser/extensions/api/commands/command_service.h

Index: chrome/browser/extensions/api/commands/command_service.h
diff --git a/chrome/browser/extensions/api/commands/command_service.h b/chrome/browser/extensions/api/commands/command_service.h
index 19cde7e4a9d7f1ade7519ca45147cbb62206c3ad..08b4fce65beee40c0f6e21647ac68d5fec4625ac 100644
--- a/chrome/browser/extensions/api/commands/command_service.h
+++ b/chrome/browser/extensions/api/commands/command_service.h
@@ -187,6 +187,8 @@ class CommandService : public BrowserContextKeyedAPI,
   void OnExtensionUninstalled(content::BrowserContext* browser_context,
                               const Extension* extension,
                               extensions::UninstallReason reason) override;
+  void OnExtensionLoaded(content::BrowserContext* browser_context,
+                                 const Extension* extension) override;
 
   // Updates keybindings for a given |extension|'s page action, browser action
   // and named commands. Assigns new keybindings and removes relinquished