third_party/protobuf: Update to HEAD (83d681ee2c)

third_party/protobuf/java/core/src/main/java/com/google/protobuf/MessageLiteToString.java

Index: third_party/protobuf/java/core/src/main/java/com/google/protobuf/MessageLiteToString.java
diff --git a/third_party/protobuf/java/core/src/main/java/com/google/protobuf/MessageLiteToString.java b/third_party/protobuf/java/core/src/main/java/com/google/protobuf/MessageLiteToString.java
index 43847651fe7ff4e711828b3b41934b4879109ba0..23373ef4cdc772ded802d18429e2f1732d9f7cd2 100644
--- a/third_party/protobuf/java/core/src/main/java/com/google/protobuf/MessageLiteToString.java
+++ b/third_party/protobuf/java/core/src/main/java/com/google/protobuf/MessageLiteToString.java
@@ -95,7 +95,7 @@ final class MessageLiteToString {
         // Try to reflectively get the value and toString() the field as if it were repeated. This
         // only works if the method names have not be proguarded out or renamed.
         Method listMethod = nameToNoArgMethod.get("get" + suffix);
-        if (listMethod != null) {
+        if (listMethod != null && listMethod.getReturnType().equals(List.class)) {
           printField(
               buffer,
               indent,
@@ -115,7 +115,7 @@ final class MessageLiteToString {
         // Heuristic to skip bytes based accessors for string fields.
         continue;
       }
-      
+
       String camelCase = suffix.substring(0, 1).toLowerCase() + suffix.substring(1);
 
       // Try to reflectively get the value and toString() the field as if it were optional. This