Update //third_party/protobuf to version 3.

third_party/protobuf/javanano/src/test/java/com/google/protobuf/nano/unittest_single_nano.proto

Index: third_party/protobuf/javanano/src/test/java/com/google/protobuf/nano/unittest_single_nano.proto
diff --git a/third_party/protobuf/src/google/protobuf/unittest_import_public_lite.proto b/third_party/protobuf/javanano/src/test/java/com/google/protobuf/nano/unittest_single_nano.proto
similarity index 90%
copy from third_party/protobuf/src/google/protobuf/unittest_import_public_lite.proto
copy to third_party/protobuf/javanano/src/test/java/com/google/protobuf/nano/unittest_single_nano.proto
index d077563cbd84d7be6daddec3f553cb564f23da0a..7de30c877d2d60bf1c758c9611dd92f2572857b4 100644
--- a/third_party/protobuf/src/google/protobuf/unittest_import_public_lite.proto
+++ b/third_party/protobuf/javanano/src/test/java/com/google/protobuf/nano/unittest_single_nano.proto
@@ -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
@@ -28,15 +28,11 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Author: liujisi@google.com (Pherl Liu)
-
+// Author: maxtroy@google.com (Max Cai)
 
 package protobuf_unittest_import;
 
-option optimize_for = LITE_RUNTIME;
-
 option java_package = "com.google.protobuf";
 
-message PublicImportMessageLite {
-  optional int32 e = 1;
+message SingleMessageNano {
 }