[ISSUE #1771]add MessageExt.getBrokerName for issue (#1772)

* typo fix

* add MessageExt.getBrokerName()

* add brokerName for toString

* get brokerName  from mq

client/src/main/java/org/apache/rocketmq/client/impl/consumer/PullAPIWrapper.java

@@ -104,6 +104,7 @@ public class PullAPIWrapper {
                     Long.toString(pullResult.getMinOffset()));
                 MessageAccessor.putProperty(msg, MessageConst.PROPERTY_MAX_OFFSET,
                     Long.toString(pullResult.getMaxOffset()));
+                msg.setBrokerName(mq.getBrokerName());
             }
 
             pullResultExt.setMsgFoundList(msgListFilterAgain);

common/src/main/java/org/apache/rocketmq/common/message/MessageExt.java

@@ -27,6 +27,8 @@ import org.apache.rocketmq.common.sysflag.MessageSysFlag;
 public class MessageExt extends Message {
     private static final long serialVersionUID = 5720810158625748049L;
 
+    private String brokerName;
+
     private int queueId;
 
     private int storeSize;
@@ -107,6 +109,14 @@ public class MessageExt extends Message {
         return socketAddress2ByteBuffer(this.storeHost, byteBuffer);
     }
 
+    public String getBrokerName() {
+        return brokerName;
+    }
+
+    public void setBrokerName(String brokerName) {
+        this.brokerName = brokerName;
+    }
+
     public int getQueueId() {
         return queueId;
     }
@@ -235,7 +245,7 @@ public class MessageExt extends Message {
 
     @Override
     public String toString() {
-        return "MessageExt [queueId=" + queueId + ", storeSize=" + storeSize + ", queueOffset=" + queueOffset
+        return "MessageExt [brokerName=" + brokerName + ", queueId=" + queueId + ", storeSize=" + storeSize + ", queueOffset=" + queueOffset
             + ", sysFlag=" + sysFlag + ", bornTimestamp=" + bornTimestamp + ", bornHost=" + bornHost
             + ", storeTimestamp=" + storeTimestamp + ", storeHost=" + storeHost + ", msgId=" + msgId
             + ", commitLogOffset=" + commitLogOffset + ", bodyCRC=" + bodyCRC + ", reconsumeTimes="