Standardize usage of virtual/override/final in chrome/browser/extensions/

chrome/browser/extensions/api/streams_private/streams_private_api.h

Index: chrome/browser/extensions/api/streams_private/streams_private_api.h
diff --git a/chrome/browser/extensions/api/streams_private/streams_private_api.h b/chrome/browser/extensions/api/streams_private/streams_private_api.h
index f416ac145c0c7c0a3790b463fa3fa72034bcedca..32f9cdfaed2bd99a71bad1e979f966c86e2313a2 100644
--- a/chrome/browser/extensions/api/streams_private/streams_private_api.h
+++ b/chrome/browser/extensions/api/streams_private/streams_private_api.h
@@ -29,7 +29,7 @@ class StreamsPrivateAPI : public BrowserContextKeyedAPI,
   static StreamsPrivateAPI* Get(content::BrowserContext* context);
 
   explicit StreamsPrivateAPI(content::BrowserContext* context);
-  virtual ~StreamsPrivateAPI();
+  ~StreamsPrivateAPI() override;
 
   // Send the onExecuteMimeTypeHandler event to |extension_id|.
   // |web_contents| is used to determine the tabId where the document is being
@@ -56,10 +56,9 @@ class StreamsPrivateAPI : public BrowserContextKeyedAPI,
                             linked_ptr<content::StreamHandle> > > StreamMap;
 
   // ExtensionRegistryObserver implementation.
-  virtual void OnExtensionUnloaded(
-      content::BrowserContext* browser_context,
-      const Extension* extension,
-      UnloadedExtensionInfo::Reason reason) override;
+  void OnExtensionUnloaded(content::BrowserContext* browser_context,
+                           const Extension* extension,
+                           UnloadedExtensionInfo::Reason reason) override;
 
   // BrowserContextKeyedAPI implementation.
   static const char* service_name() {
@@ -85,10 +84,10 @@ class StreamsPrivateAbortFunction : public UIThreadExtensionFunction {
   DECLARE_EXTENSION_FUNCTION("streamsPrivate.abort", STREAMSPRIVATE_ABORT)
 
  protected:
-  virtual ~StreamsPrivateAbortFunction() {}
+  ~StreamsPrivateAbortFunction() override {}
 
   // ExtensionFunction:
-  virtual ExtensionFunction::ResponseAction Run() override;
+  ExtensionFunction::ResponseAction Run() override;
 
  private:
   void OnClose();