Standardize usage of virtual/override/final specifiers.

chrome/browser/ui/views/frame/opaque_browser_frame_view_linux.h

Index: chrome/browser/ui/views/frame/opaque_browser_frame_view_linux.h
diff --git a/chrome/browser/ui/views/frame/opaque_browser_frame_view_linux.h b/chrome/browser/ui/views/frame/opaque_browser_frame_view_linux.h
index c2074a2dad1a67e4e91667a817a8131534d50c09..935e7801f61b7a21cdfaa85cae6cc391a5950045 100644
--- a/chrome/browser/ui/views/frame/opaque_browser_frame_view_linux.h
+++ b/chrome/browser/ui/views/frame/opaque_browser_frame_view_linux.h
@@ -22,13 +22,13 @@ class OpaqueBrowserFrameViewLinux
       OpaqueBrowserFrameView* view,
       OpaqueBrowserFrameViewLayout* layout,
       Profile* profile);
-  virtual ~OpaqueBrowserFrameViewLinux();
+  ~OpaqueBrowserFrameViewLinux() override;
 
   // Overridden from OpaqueBrowserFrameViewPlatformSpecific:
-  virtual bool IsUsingSystemTheme() override;
+  bool IsUsingSystemTheme() override;
 
   // Overridden from views::WindowButtonOrderObserver:
-  virtual void OnWindowButtonOrderingChange(
+  void OnWindowButtonOrderingChange(
       const std::vector<views::FrameButton>& leading_buttons,
       const std::vector<views::FrameButton>& trailing_buttons) override;