JIRA: https://jira.spring.io/browse/INT-3598
- Force the first two constructor args to be of type `String`.
- When no client factory, add one in the parser rather than selecing an alternate ctor.
Conflicts:
spring-integration-mqtt/src/main/java/org/springframework/integration/mqtt/config/xml/MqttParserUtils.java
spring-integration-mqtt/src/test/java/org/springframework/integration/mqtt/config/xml/MqttMessageDrivenChannelAdapterParserTests-context.xml
spring-integration-mqtt/src/test/java/org/springframework/integration/mqtt/config/xml/MqttMessageDrivenChannelAdapterParserTests.java
Remove test for unsupported `empty topics` functionality
2231f1d68f