THRIFT-4480 - Handle seqid = 0
Client: js

This closes #1487
diff --git a/lib/nodejs/lib/thrift/binary_protocol.js b/lib/nodejs/lib/thrift/binary_protocol.js
index 0c0ee50..b57c8c5 100644
--- a/lib/nodejs/lib/thrift/binary_protocol.js
+++ b/lib/nodejs/lib/thrift/binary_protocol.js
@@ -37,6 +37,7 @@
   this.trans = trans;
   this.strictRead = (strictRead !== undefined ? strictRead : false);
   this.strictWrite = (strictWrite !== undefined ? strictWrite : true);
+  this._seqid = null;
 };
 
 TBinaryProtocol.prototype.flush = function() {
@@ -54,7 +55,7 @@
       this.writeI32(seqid);
     }
     // Record client seqid to find callback again
-    if (this._seqid) {
+    if (this._seqid !== null) {
       log.warning('SeqId already set', { 'name': name });
     } else {
       this._seqid = seqid;
@@ -63,7 +64,7 @@
 };
 
 TBinaryProtocol.prototype.writeMessageEnd = function() {
-    if (this._seqid) {
+    if (this._seqid !== null) {
         this._seqid = null;
     } else {
         log.warning('No seqid to unset');