| Index: tracing/tracing/ui/base/dropdown.html | 
| diff --git a/tracing/tracing/ui/base/dropdown.html b/tracing/tracing/ui/base/dropdown.html | 
| index df9099f82f8f9621935d190e1f197af5a4a65e34..5c2f4dfe170a93e5a61bf150611ab957c8d7ea68 100644 | 
| --- a/tracing/tracing/ui/base/dropdown.html | 
| +++ b/tracing/tracing/ui/base/dropdown.html | 
| @@ -118,7 +118,7 @@ Polymer({ | 
| if (this.isOpen) | 
| return; | 
|  | 
| -    this.$.outer.classList.add('open'); | 
| +    Polymer.dom(this.$.outer).classList.add('open'); | 
|  | 
| var ddr = this.$.outer.getBoundingClientRect(); | 
| var rW = Math.max(ddr.width, 150); | 
| @@ -149,7 +149,7 @@ Polymer({ | 
| if (!this.isOpen) | 
| return; | 
| this.$.dialog.close(); | 
| -    this.$.outer.classList.remove('open'); | 
| +    Polymer.dom(this.$.outer).classList.remove('open'); | 
| this.$.outer.focus(); | 
| }, | 
|  | 
|  |