third_party/protobuf: Update to HEAD (83d681ee2c)

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

Index: third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_field.h
diff --git a/third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_field.h b/third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_field.h
index 3b01252780da26393e0056c802f068bea1b7f044..00dc25d4cf5a5e26d441aff6b955b54f218eec10 100644
--- a/third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_field.h
+++ b/third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_field.h
@@ -61,11 +61,11 @@ namespace cpp {
 // ['name', 'index', 'number', 'classname', 'declared_type', 'tag_size',
 // 'deprecation'].
 void SetCommonFieldVariables(const FieldDescriptor* descriptor,
-                             map<string, string>* variables,
+                             std::map<string, string>* variables,
                              const Options& options);
 
 void SetCommonOneofFieldVariables(const FieldDescriptor* descriptor,
-                                  map<string, string>* variables);
+                                  std::map<string, string>* variables);
 
 class FieldGenerator {
  public:
@@ -124,10 +124,20 @@ class FieldGenerator {
     io::Printer* /*printer*/) const {}
 
   // Generate lines of code (statements, not declarations) which clear the
-  // field.  This is used to define the clear_$name$() method as well as
-  // the Clear() method for the whole message.
+  // field.  This is used to define the clear_$name$() method
   virtual void GenerateClearingCode(io::Printer* printer) const = 0;
 
+  // Generate lines of code (statements, not declarations) which clear the field
+  // as part of the Clear() method for the whole message.  For message types
+  // which have field presence bits, MessageGenerator::GenerateClear will have
+  // already checked the presence bits.
+  //
+  // Since most field types can re-use GenerateClearingCode, this method is not
+  // pure virtual.
+  virtual void GenerateMessageClearingCode(io::Printer* printer) const {
+    GenerateClearingCode(printer);
+  }
+
   // Generate lines of code (statements, not declarations) which merges the
   // contents of the field from the current message to the target message,
   // which is stored in the generated code variable "from".
@@ -136,6 +146,9 @@ class FieldGenerator {
   // GenerateMergeFrom method.
   virtual void GenerateMergingCode(io::Printer* printer) const = 0;
 
+  // Generates a copy constructor
+  virtual void GenerateCopyConstructorCode(io::Printer* printer) const = 0;
+
   // Generate lines of code (statements, not declarations) which swaps
   // this field and the corresponding field of another message, which
   // is stored in the generated code variable "other". This is used to