Update //third_party/protobuf to version 3.

third_party/protobuf/examples/list_people.cc

+// See README.txt for information and build instructions.
+
+#include <iostream>
+#include <fstream>
+#include <string>
+#include "addressbook.pb.h"
+using namespace std;
+
+// Iterates though all people in the AddressBook and prints info about them.
+void ListPeople(const tutorial::AddressBook& address_book) {
+  for (int i = 0; i < address_book.people_size(); i++) {
+    const tutorial::Person& person = address_book.people(i);
+
+    cout << "Person ID: " << person.id() << endl;
+    cout << "  Name: " << person.name() << endl;
+    if (person.email() != "") {
+      cout << "  E-mail address: " << person.email() << endl;
+    }
+
+    for (int j = 0; j < person.phones_size(); j++) {
+      const tutorial::Person::PhoneNumber& phone_number = person.phones(j);
+
+      switch (phone_number.type()) {
+        case tutorial::Person::MOBILE:
+          cout << "  Mobile phone #: ";
+          break;
+        case tutorial::Person::HOME:
+          cout << "  Home phone #: ";
+          break;
+        case tutorial::Person::WORK:
+          cout << "  Work phone #: ";
+          break;
+      }
+      cout << phone_number.number() << endl;
+    }
+  }
+}
+
+// Main function:  Reads the entire address book from a file and prints all
+//   the information inside.
+int main(int argc, char* argv[]) {
+  // Verify that the version of the library that we linked against is
+  // compatible with the version of the headers we compiled against.
+  GOOGLE_PROTOBUF_VERIFY_VERSION;
+
+  if (argc != 2) {
+    cerr << "Usage:  " << argv[0] << " ADDRESS_BOOK_FILE" << endl;
+    return -1;
+  }
+
+  tutorial::AddressBook address_book;
+
+  {
+    // Read the existing address book.
+    fstream input(argv[1], ios::in | ios::binary);
+    if (!address_book.ParseFromIstream(&input)) {
+      cerr << "Failed to parse address book." << endl;
+      return -1;
+    }
+  }
+
+  ListPeople(address_book);
+
+  // Optional:  Delete all global objects allocated by libprotobuf.
+  google::protobuf::ShutdownProtobufLibrary();
+
+  return 0;
+}