Update {virtual,override} to follow C++11 style in content.

content/renderer/java/gin_java_bridge_value_converter.cc

Index: content/renderer/java/gin_java_bridge_value_converter.cc
diff --git a/content/renderer/java/gin_java_bridge_value_converter.cc b/content/renderer/java/gin_java_bridge_value_converter.cc
index 64860822e0725b82d4f367f4b312a17be6dcfd90..c8bd877ad5c2ca41778afc0a9643cd36f3d35e73 100644
--- a/content/renderer/java/gin_java_bridge_value_converter.cc
+++ b/content/renderer/java/gin_java_bridge_value_converter.cc
@@ -73,7 +73,7 @@ class TypedArraySerializerImpl : public TypedArraySerializer {
         new TypedArraySerializerImpl<ElementType, ListType>(typed_array));
   }
 
-  virtual void serializeTo(char* data,
+  void serializeTo(char* data,
                    size_t data_length,
                    base::ListValue* out) override {
     DCHECK_EQ(data_length, typed_array_->Length() * sizeof(ElementType));