[Media Router WebUI] Handle header height changes.

chrome/browser/resources/media_router/elements/media_router_header/media_router_header.js

Index: chrome/browser/resources/media_router/elements/media_router_header/media_router_header.js
diff --git a/chrome/browser/resources/media_router/elements/media_router_header/media_router_header.js b/chrome/browser/resources/media_router/elements/media_router_header/media_router_header.js
index 73b6b1982bed5eeb87c6d44ce1cb6aa5e0bf5369..c9581d2b591ca9293d1c8d4cc076e28870ab5697 100644
--- a/chrome/browser/resources/media_router/elements/media_router_header/media_router_header.js
+++ b/chrome/browser/resources/media_router/elements/media_router_header/media_router_header.js
@@ -46,6 +46,16 @@ Polymer({
     },
 
     /**
+     * The height of the header when it doesn't show the user email.
+     * @private {number}
+     */
+    headerWithoutEmailHeight_: {
+      type: Number,
+      readOnly: true,
+      value: 52,
+    },
+
+    /**
      * Whether to show the user email in the header.
      * @type {boolean}
      */
@@ -216,7 +226,8 @@ Polymer({
 
       this.$$('#header-toolbar').style.height =
           this.showEmail && !this.isEmptyOrWhitespace_(this.userEmail) ?
-              this.headerWithEmailHeight_ + 'px' : undefined;
+              this.headerWithEmailHeight_ + 'px' :
+                  this.headerWithoutEmailHeight_ + 'px';

[amp, 2016/03/24 19:06:53]

Thanks for updating this.  I thought I had verified that setting this back to
undefined properly reset the css back to the default, but maybe I missed it or
something changed since this first went in.

 
       // Only fire if height actually changed.
       if (currentHeight != this.offsetHeight) {