third_party/protobuf: Update to HEAD (83d681ee2c)

third_party/protobuf/src/google/protobuf/util/message_differencer.cc

Index: third_party/protobuf/src/google/protobuf/util/message_differencer.cc
diff --git a/third_party/protobuf/src/google/protobuf/util/message_differencer.cc b/third_party/protobuf/src/google/protobuf/util/message_differencer.cc
index fe8119bf3d54d972fa7131b7547d2217256dfd81..328b40d8e36b7a1d1fb2f4811f8c82022c96b9bb 100644
--- a/third_party/protobuf/src/google/protobuf/util/message_differencer.cc
+++ b/third_party/protobuf/src/google/protobuf/util/message_differencer.cc
@@ -474,7 +474,10 @@ bool MessageDifferencer::Compare(
 
   // Retrieve all the set fields, including extensions.
   vector<const FieldDescriptor*> message1_fields;
+  message1_fields.reserve(1 + message1.GetDescriptor()->field_count());
+
   vector<const FieldDescriptor*> message2_fields;
+  message2_fields.reserve(1 + message2.GetDescriptor()->field_count());
 
   reflection1->ListFields(message1, &message1_fields);
   reflection2->ListFields(message2, &message2_fields);
@@ -623,6 +626,7 @@ bool MessageDifferencer::CompareWithFieldsInternal(
       }
 
       if (reporter_ != NULL) {
+        assert(field1 != NULL);
         int count = field1->is_repeated() ?
             reflection1->FieldSize(message1, field1) : 1;
 
@@ -703,6 +707,7 @@ bool MessageDifferencer::CompareWithFieldsInternal(
     }
 
     bool fieldDifferent = false;
+    assert(field1 != NULL);
     if (field1->is_repeated()) {
       fieldDifferent = !CompareRepeatedField(message1, message2, field1,
                                              parent_fields);
@@ -872,6 +877,7 @@ bool MessageDifferencer::CompareRepeatedField(
 
   for (int i = 0; i < count1; ++i) {
     if (match_list1[i] != -1) continue;
+    assert(reporter_ != NULL);
     specific_field.index = i;
     parent_fields->push_back(specific_field);
     reporter_->ReportDeleted(message1, message2, *parent_fields);
@@ -1383,11 +1389,10 @@ bool MessageDifferencer::MatchRepeatedFieldIndices(
   if (key_comparator != NULL || IsTreatedAsSet(repeated_field)) {
     if (scope_ == PARTIAL) {
       // When partial matching is enabled, Compare(a, b) && Compare(a, c)
-      // doesn't neccessarily imply Compare(b, c). Therefore a naive greedy
+      // doesn't necessarily imply Compare(b, c). Therefore a naive greedy
       // algorithm will fail to find a maximum matching.
       // Here we use the argumenting path algorithm.
-      MaximumMatcher::NodeMatchCallback* callback =
-          ::google::protobuf::internal::NewPermanentCallback(
+      MaximumMatcher::NodeMatchCallback* callback = NewPermanentCallback(
               this, &MessageDifferencer::IsMatch,
               repeated_field, key_comparator,
               &message1, &message2, parent_fields);