Update protobuf to r428, part 1.

third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_string_field.h

Index: third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_string_field.h
===================================================================
--- third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_string_field.h	(revision 216642)
+++ third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_string_field.h	(working copy)
@@ -46,7 +46,8 @@
 
 class StringFieldGenerator : public FieldGenerator {
  public:
-  explicit StringFieldGenerator(const FieldDescriptor* descriptor);
+  explicit StringFieldGenerator(const FieldDescriptor* descriptor,
+                                const Options& options);
   ~StringFieldGenerator();
 
   // implements FieldGenerator ---------------------------------------
@@ -59,6 +60,8 @@
   void GenerateSwappingCode(io::Printer* printer) const;
   void GenerateConstructorCode(io::Printer* printer) const;
   void GenerateDestructorCode(io::Printer* printer) const;
+  void GenerateDefaultInstanceAllocator(io::Printer* printer) const;
+  void GenerateShutdownCode(io::Printer* printer) const;
   void GenerateMergeFromCodedStream(io::Printer* printer) const;
   void GenerateSerializeWithCachedSizes(io::Printer* printer) const;
   void GenerateSerializeWithCachedSizesToArray(io::Printer* printer) const;
@@ -73,7 +76,8 @@
 
 class RepeatedStringFieldGenerator : public FieldGenerator {
  public:
-  explicit RepeatedStringFieldGenerator(const FieldDescriptor* descriptor);
+  explicit RepeatedStringFieldGenerator(const FieldDescriptor* descriptor,
+                                        const Options& options);
   ~RepeatedStringFieldGenerator();
 
   // implements FieldGenerator ---------------------------------------