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

The Google style guide states that only one of {virtual,override,final} should be used for each declaration, since override implies virtual and final implies both virtual and override.

This patch was manually generated using a regex and a text editor.

BUG=417463

Review URL: https://codereview.chromium.org/1094903006

Cr-Commit-Position: refs/heads/master@{#326392}
diff --git a/base/json/json_value_converter.h b/base/json/json_value_converter.h
index c4bfe61..f94d46e3 100644
--- a/base/json/json_value_converter.h
+++ b/base/json/json_value_converter.h
@@ -123,8 +123,7 @@
         value_converter_(converter) {
   }
 
-  virtual bool ConvertField(
-      const base::Value& value, StructType* dst) const override {
+  bool ConvertField(const base::Value& value, StructType* dst) const override {
     return value_converter_->Convert(value, &(dst->*field_pointer_));
   }
 
@@ -202,8 +201,7 @@
   ValueFieldConverter(ConvertFunc convert_func)
       : convert_func_(convert_func) {}
 
-  virtual bool Convert(const base::Value& value,
-                       FieldType* field) const override {
+  bool Convert(const base::Value& value, FieldType* field) const override {
     return convert_func_(&value, field);
   }
 
@@ -221,8 +219,7 @@
   CustomFieldConverter(ConvertFunc convert_func)
       : convert_func_(convert_func) {}
 
-  virtual bool Convert(const base::Value& value,
-                       FieldType* field) const override {
+  bool Convert(const base::Value& value, FieldType* field) const override {
     std::string string_value;
     return value.GetAsString(&string_value) &&
         convert_func_(string_value, field);
@@ -239,8 +236,7 @@
  public:
   NestedValueConverter() {}
 
-  virtual bool Convert(
-      const base::Value& value, NestedType* field) const override {
+  bool Convert(const base::Value& value, NestedType* field) const override {
     return converter_.Convert(value, field);
   }
 
@@ -254,8 +250,8 @@
  public:
   RepeatedValueConverter() {}
 
-  virtual bool Convert(
-      const base::Value& value, ScopedVector<Element>* field) const override {
+  bool Convert(const base::Value& value,
+               ScopedVector<Element>* field) const override {
     const base::ListValue* list = NULL;
     if (!value.GetAsList(&list)) {
       // The field is not a list.
@@ -290,8 +286,8 @@
  public:
   RepeatedMessageConverter() {}
 
-  virtual bool Convert(const base::Value& value,
-                       ScopedVector<NestedType>* field) const override {
+  bool Convert(const base::Value& value,
+               ScopedVector<NestedType>* field) const override {
     const base::ListValue* list = NULL;
     if (!value.GetAsList(&list))
       return false;
@@ -327,8 +323,8 @@
   RepeatedCustomValueConverter(ConvertFunc convert_func)
       : convert_func_(convert_func) {}
 
-  virtual bool Convert(const base::Value& value,
-                       ScopedVector<NestedType>* field) const override {
+  bool Convert(const base::Value& value,
+               ScopedVector<NestedType>* field) const override {
     const base::ListValue* list = NULL;
     if (!value.GetAsList(&list))
       return false;