Revert https://codereview.chromium.org/1291903002 (protobuf roll).

third_party/protobuf/src/google/protobuf/io/zero_copy_stream_impl.cc

Index: third_party/protobuf/src/google/protobuf/io/zero_copy_stream_impl.cc
diff --git a/third_party/protobuf/src/google/protobuf/io/zero_copy_stream_impl.cc b/third_party/protobuf/src/google/protobuf/io/zero_copy_stream_impl.cc
index f7901b2797eb133cb6acab9e9630dfcdeb1b6827..9fcbb622a36f5998f129948346d2f6b18ae35652 100644
--- a/third_party/protobuf/src/google/protobuf/io/zero_copy_stream_impl.cc
+++ b/third_party/protobuf/src/google/protobuf/io/zero_copy_stream_impl.cc
@@ -1,6 +1,6 @@
 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
+// http://code.google.com/p/protobuf/
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
@@ -413,9 +413,7 @@ int64 ConcatenatingInputStream::ByteCount() const {
 
 LimitingInputStream::LimitingInputStream(ZeroCopyInputStream* input,
                                          int64 limit)
-  : input_(input), limit_(limit) {
-  prior_bytes_read_ = input_->ByteCount();
-}
+  : input_(input), limit_(limit) {}
 
 LimitingInputStream::~LimitingInputStream() {
   // If we overshot the limit, back up.
@@ -459,9 +457,9 @@ bool LimitingInputStream::Skip(int count) {
 
 int64 LimitingInputStream::ByteCount() const {
   if (limit_ < 0) {
-    return input_->ByteCount() + limit_ - prior_bytes_read_;
+    return input_->ByteCount() + limit_;
   } else {
-    return input_->ByteCount() - prior_bytes_read_;
+    return input_->ByteCount();
   }
 }