Standardize usage of virtual/override/final in content/renderer/

This patch was automatically generated by applying clang fixit hints
generated by the plugin to the source tree.

BUG=417463
[email protected]

Review URL: https://codereview.chromium.org/670683003

Cr-Commit-Position: refs/heads/master@{#300473}
diff --git a/content/renderer/skia_benchmarking_extension.h b/content/renderer/skia_benchmarking_extension.h
index 716378d..2e0faf16 100644
--- a/content/renderer/skia_benchmarking_extension.h
+++ b/content/renderer/skia_benchmarking_extension.h
@@ -28,10 +28,10 @@
 
  private:
   SkiaBenchmarking();
-  virtual ~SkiaBenchmarking();
+  ~SkiaBenchmarking() override;
 
   // gin::Wrappable.
-  virtual gin::ObjectTemplateBuilder GetObjectTemplateBuilder(
+  gin::ObjectTemplateBuilder GetObjectTemplateBuilder(
       v8::Isolate* isolate) override;
 
   // Rasterizes a Picture JSON-encoded by cc::Picture::AsValue().