Standardize usage of virtual/override/final in content/

content/shell/common/shell_content_client.h

Index: content/shell/common/shell_content_client.h
diff --git a/content/shell/common/shell_content_client.h b/content/shell/common/shell_content_client.h
index 6d928fed0373e27f71ae1fd2eac61d037b764cbb..9ea4fb5b72951437656d7d96bb9e47e624364149 100644
--- a/content/shell/common/shell_content_client.h
+++ b/content/shell/common/shell_content_client.h
@@ -17,16 +17,16 @@ std::string GetShellUserAgent();
 
 class ShellContentClient : public ContentClient {
  public:
-  virtual ~ShellContentClient();
+  ~ShellContentClient() override;
 
-  virtual std::string GetUserAgent() const override;
-  virtual base::string16 GetLocalizedString(int message_id) const override;
-  virtual base::StringPiece GetDataResource(
+  std::string GetUserAgent() const override;
+  base::string16 GetLocalizedString(int message_id) const override;
+  base::StringPiece GetDataResource(
       int resource_id,
       ui::ScaleFactor scale_factor) const override;
-  virtual base::RefCountedStaticMemory* GetDataResourceBytes(
+  base::RefCountedStaticMemory* GetDataResourceBytes(
       int resource_id) const override;
-  virtual gfx::Image& GetNativeImageNamed(int resource_id) const override;
+  gfx::Image& GetNativeImageNamed(int resource_id) const override;
 };
 
 }  // namespace content