action bubbling weirdness

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName:'Ember Twiddle',
  
  actions: {
    reportClick(element) {
      alert(element);
    }
  }
});

application.template.hbs

<h1>Welcome to {{appName}}</h1>

<div class="outer-el" onclick={{action (action "reportClick" "A outer")}}> 
  A (both have "onclick")
  <div class="inner-el" onclick={{action (action "reportClick" "A inner") bubbles=false}}>*</div>
</div>

<div class="outer-el" onclick={{action (action "reportClick" "B outer")}}> 
  B (outer has "onclick")
  <div class="inner-el" {{action (action "reportClick" "B inner") bubbles=false}}>*</div>
</div>

<div class="outer-el" {{action (action "reportClick" "C outer")}}> 
  C (inner has "onclick")
  <div class="inner-el" onclick={{action (action "reportClick" "C inner") bubbles=false}}>*</div>
</div>

<div class="outer-el" {{action (action "reportClick" "D outer")}}>
  D (no onclick)
  <div class="inner-el inner-el--d" {{action (action "reportClick" "D inner") bubbles=false}}>*</div>
</div>

styles.app.css

body {
  margin: 12px 16px;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 12pt;
}

.outer-el {
  border-radius: 3px;
  border: 1px solid black;
  background: hsl(0, 0%, 90%);
  cursor: pointer;
  display: inline-block;
  padding: 10px;
  margin-top: 12px;
}

.outer-el:hover {
  background: hsl(0, 0%, 98%);
}

.inner-el {
  border-radius: 3px;
  background: hsl(0, 100%, 50%);
  color: white;
  cursor: pointer;
	display: inline-block; 
  width: 20px;
  height: 20px;
  line-height: 20px;
  text-align: center;
}

.inner-el:hover {
  background: hsl(0, 100%, 40%);
}

.inner-el--d {
  background: hsl(100, 100%, 40%);
}

.inner-el--d:hover {
  background: hsl(100, 100%, 30%);
}

twiddle.json

{
  "version": "0.4.16",
  "EmberENV": {
    "FEATURES": {}
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.1.0",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.1.0/ember-data.js",
    "ember-template-compiler": "2.1.0"
  }
}