java.util.ConcurrentModificationException starting ear files with the release of Apache Tomee Plus 7.1.2

Question

With the release of Apache TomEE Plus 7.1.2, our application is not starting. It starts in 7.1.1. I narrowed it down to this code change in org.apache.openejb.assembler.classic.Assembler.createApplication method at line 829. It seems to only happen when there are multiple web modules defined in the application.xml. I can't find any doc on why this was introduced.

 for (Map.Entry entry : appContext.getProperties().entrySet()) {
      if (Module.class.isInstance(entry.getValue())) {
        appContext.getProperties().remove(entry.getKey());
      }
    }

One thing to note is if I put the 7.1.1 version of the openejb-core jar, the error goes away. Here is the stacktrace.

org.apache.openejb.OpenEJBException: Creating application failed: C:\apps\apache-tomee-plus-7.1.2\apps\ourApplication: null
        at org.apache.openejb.assembler.classic.Assembler.createApplication(Assembler.java:1101)
        at org.apache.openejb.assembler.classic.Assembler.createApplication(Assembler.java:755)
        at org.apache.openejb.assembler.classic.Assembler.buildContainerSystem(Assembler.java:633)
        at org.apache.openejb.assembler.classic.Assembler.build(Assembler.java:485)
        at org.apache.openejb.OpenEJB$Instance.<init>(OpenEJB.java:150)
        at org.apache.openejb.OpenEJB.init(OpenEJB.java:307)
        at org.apache.tomee.catalina.TomcatLoader.initialize(TomcatLoader.java:247)
        at org.apache.tomee.catalina.ServerListener.lifecycleEvent(ServerListener.java:168)
        at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:123)
        at org.apache.catalina.util.LifecycleBase.setStateInternal(LifecycleBase.java:423)
        at org.apache.catalina.util.LifecycleBase.init(LifecycleBase.java:137)
        at org.apache.catalina.startup.Catalina.load(Catalina.java:639)
        at org.apache.catalina.startup.Catalina.load(Catalina.java:662)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.catalina.startup.Bootstrap.load(Bootstrap.java:303)
        at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:473)
    Caused by: java.util.ConcurrentModificationException
        at java.util.LinkedHashMap$LinkedHashIterator.nextNode(LinkedHashMap.java:719)
        at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:752)
        at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:750)
        at java.util.Collections$UnmodifiableCollection$1.next(Collections.java:1042)
        at org.apache.openejb.assembler.classic.Assembler.createApplication(Assembler.java:829)
        ... 18 more