title: NgStyle returns: ERROR Error: Cannot find a differ supporting object '{"background-color":"blue"}'
body: <p>With this in my template,</p>
  
  <pre><code>&lt;span [ngStyle]="myStyle()"&gt; HELLO &lt;/span&gt;
  </code></pre>
  
  <p>And this in my component,</p>
  
  <pre><code>myStyle(): string {
    return '{"background-color":"blue"}'
  } 
  </code></pre>
  
  <p>I'm getting </p>
  
  <pre><code>ERROR Error: Cannot find a differ supporting object '{"background-color":"blue"}'
      at KeyValueDiffers.webpackJsonp.../../../core/@angular/core.es5.js.KeyValueDiffers.find (core.es5.js:8051)
      at NgStyle.set [as ngStyle] (common.es5.js:2441)
      at updateProp (core.es5.js:11114)
      at checkAndUpdateDirectiveInline (core.es5.js:10806)
      at checkAndUpdateNodeInline (core.es5.js:12349)
      at checkAndUpdateNode (core.es5.js:12288)
      at debugCheckAndUpdateNode (core.es5.js:13149)
      at debugCheckDirectivesFn (core.es5.js:13090)
      at Object.View_AppComponent_2.currVal_2 [as updateDirectives] (AppComponent.html:10)
      at Object.debugUpdateDirectives [as updateDirectives] (core.es5.js:13075)
  View_AppComponent_2 @ AppComponent.html:10
  webpackJsonp.../../../core/@angular/core.es5.js.DebugContext_.logError @ core.es5.js:13415
  </code></pre>