Update //third_party/protobuf to version 3.

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

Index: third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_helpers.h
diff --git a/third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_helpers.h b/third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_helpers.h
index 1b5b1ac9ca8d14aaf45feb19f3d408d863b78fac..a22d414d022fb9c10744e7dc2a8a5bcfa173f31c 100644
--- a/third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_helpers.h
+++ b/third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_helpers.h
@@ -1,6 +1,6 @@
 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 Google Inc.  All rights reserved.
-// http://code.google.com/p/protobuf/
+// https://developers.google.com/protocol-buffers/
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
@@ -66,14 +66,28 @@ extern const char kThinSeparator[];
 string ClassName(const Descriptor* descriptor, bool qualified);
 string ClassName(const EnumDescriptor* enum_descriptor, bool qualified);
 
+// Name of the CRTP class template (for use with proto_h).
+// This is a class name, like "ProtoName_InternalBase".
+string DependentBaseClassTemplateName(const Descriptor* descriptor);
+
+// Name of the base class: either the dependent base class (for use with
+// proto_h) or google::protobuf::Message.
 string SuperClassName(const Descriptor* descriptor);
 
+// Returns a string that down-casts from the dependent base class to the
+// derived class.
+string DependentBaseDownCast();
+string DependentBaseConstDownCast();
+
 // Get the (unqualified) name that should be used for this field in C++ code.
 // The name is coerced to lower-case to emulate proto1 behavior.  People
 // should be using lowercase-with-underscores style for proto field names
 // anyway, so normally this just returns field->name().
 string FieldName(const FieldDescriptor* field);
 
+// Get the sanitized name that should be used for the given enum in C++ code.
+string EnumValueName(const EnumValueDescriptor* enum_value);
+
 // Get the unqualified name that should be used for a field's field
 // number constant.
 string FieldConstantName(const FieldDescriptor *field);
@@ -85,6 +99,20 @@ inline const Descriptor* FieldScope(const FieldDescriptor* field) {
     field->extension_scope() : field->containing_type();
 }
 
+// Returns true if the given 'field_descriptor' has a message type that is
+// a dependency of the file where the field is defined (i.e., the field
+// type is defined in a different file than the message holding the field).
+//
+// This only applies to Message-typed fields. Enum-typed fields may refer
+// to an enum in a dependency; however, enums are specified and
+// forward-declared with an enum-base, so the definition is not required to
+// manipulate the field value.
+bool IsFieldDependent(const FieldDescriptor* field_descriptor);
+
+// Returns the name that should be used for forcing dependent lookup from a
+// dependent base class.
+string DependentTypeName(const FieldDescriptor* field);
+
 // Returns the fully-qualified type name field->message_type().  Usually this
 // is just ClassName(field->message_type(), true);
 string FieldMessageTypeName(const FieldDescriptor* field);
@@ -103,6 +131,12 @@ const char* PrimitiveTypeName(FieldDescriptor::CppType type);
 // methods of WireFormat.  For example, TYPE_INT32 becomes "Int32".
 const char* DeclaredTypeMethodName(FieldDescriptor::Type type);
 
+// Return the code that evaluates to the number when compiled.
+string Int32ToString(int number);
+
+// Return the code that evaluates to the number when compiled.
+string Int64ToString(int64 number);
+
 // Get code that evaluates to the field's default value.
 string DefaultValue(const FieldDescriptor* field);
 
@@ -115,18 +149,38 @@ string GlobalAddDescriptorsName(const string& filename);
 // Return the name of the AssignDescriptors() function for a given file.
 string GlobalAssignDescriptorsName(const string& filename);
 
+// Return the qualified C++ name for a file level symbol.
+string QualifiedFileLevelSymbol(const string& package, const string& name);
+
 // Return the name of the ShutdownFile() function for a given file.
 string GlobalShutdownFileName(const string& filename);
 
 // Escape C++ trigraphs by escaping question marks to \?
 string EscapeTrigraphs(const string& to_escape);
 
-// Do message classes in this file keep track of unknown fields?
-inline bool HasUnknownFields(const FileDescriptor* file) {
-  return file->options().optimize_for() != FileOptions::LITE_RUNTIME ||
-         file->options().retain_unknown_fields();
+// Escaped function name to eliminate naming conflict.
+string SafeFunctionName(const Descriptor* descriptor,
+                        const FieldDescriptor* field,
+                        const string& prefix);
+
+// Returns true if unknown fields are preseved after parsing.
+inline bool PreserveUnknownFields(const Descriptor* message) {
+  return message->file()->syntax() != FileDescriptor::SYNTAX_PROTO3;
 }
 
+// If PreserveUnknownFields() is true, determines whether unknown
+// fields will be stored in an UnknownFieldSet or a string.
+// If PreserveUnknownFields() is false, this method will not be
+// used.
+inline bool UseUnknownFieldSet(const FileDescriptor* file) {
+  return file->options().optimize_for() != FileOptions::LITE_RUNTIME;
+}
+
+
+// Does the file have any map fields, necessitating the file to include
+// map_field_inl.h and map.h.
+bool HasMapFields(const FileDescriptor* file);
+
 // Does this file have any enum type definitions?
 bool HasEnumDefinitions(const FileDescriptor* file);
 
@@ -136,7 +190,7 @@ inline bool HasGeneratedMethods(const FileDescriptor* file) {
   return file->options().optimize_for() != FileOptions::CODE_SIZE;
 }
 
-// Do message classes in this file have descriptor and refelction methods?
+// Do message classes in this file have descriptor and reflection methods?
 inline bool HasDescriptorMethods(const FileDescriptor* file) {
   return file->options().optimize_for() != FileOptions::LITE_RUNTIME;
 }
@@ -148,11 +202,6 @@ inline bool HasGenericServices(const FileDescriptor* file) {
          file->options().cc_generic_services();
 }
 
-// Should string fields in this file verify that their contents are UTF-8?
-inline bool HasUtf8Verification(const FileDescriptor* file) {
-  return file->options().optimize_for() != FileOptions::LITE_RUNTIME;
-}
-
 // Should we generate a separate, super-optimized code path for serializing to
 // flat arrays?  We don't do this in Lite mode because we'd rather reduce code
 // size.
@@ -178,6 +227,60 @@ void PrintHandlingOptionalStaticInitializers(
     const char* without_static_init);
 
 
+inline bool IsMapEntryMessage(const Descriptor* descriptor) {
+  return descriptor->options().map_entry();
+}
+
+// Returns true if the field's CPPTYPE is string or message.
+bool IsStringOrMessage(const FieldDescriptor* field);
+
+// For a string field, returns the effective ctype.  If the actual ctype is
+// not supported, returns the default of STRING.
+FieldOptions::CType EffectiveStringCType(const FieldDescriptor* field);
+
+string UnderscoresToCamelCase(const string& input, bool cap_next_letter);
+
+inline bool HasFieldPresence(const FileDescriptor* file) {
+  return file->syntax() != FileDescriptor::SYNTAX_PROTO3;
+}
+
+// Returns true if 'enum' semantics are such that unknown values are preserved
+// in the enum field itself, rather than going to the UnknownFieldSet.
+inline bool HasPreservingUnknownEnumSemantics(const FileDescriptor* file) {
+  return file->syntax() == FileDescriptor::SYNTAX_PROTO3;
+}
+
+inline bool SupportsArenas(const FileDescriptor* file) {
+  return file->options().cc_enable_arenas();
+}
+
+inline bool SupportsArenas(const Descriptor* desc) {
+  return SupportsArenas(desc->file());
+}
+
+inline bool SupportsArenas(const FieldDescriptor* field) {
+  return SupportsArenas(field->file());
+}
+
+bool IsAnyMessage(const FileDescriptor* descriptor);
+bool IsAnyMessage(const Descriptor* descriptor);
+
+bool IsWellKnownMessage(const FileDescriptor* descriptor);
+
+void GenerateUtf8CheckCodeForString(
+    const FieldDescriptor* field,
+    bool for_parse,
+    const map<string, string>& variables,
+    const char* parameters,
+    io::Printer* printer);
+
+void GenerateUtf8CheckCodeForCord(
+    const FieldDescriptor* field,
+    bool for_parse,
+    const map<string, string>& variables,
+    const char* parameters,
+    io::Printer* printer);
+
 }  // namespace cpp
 }  // namespace compiler
 }  // namespace protobuf