MD Settings: About page, hooking up channel switcher dialog.

chrome/browser/resources/settings/about_page/detailed_build_info.js

Index: chrome/browser/resources/settings/about_page/detailed_build_info.js
diff --git a/chrome/browser/resources/settings/about_page/detailed_build_info.js b/chrome/browser/resources/settings/about_page/detailed_build_info.js
index 613d650660f589f129c60263c1b6bf4b0165f679..acb722e5baae46634e37cbb72714643ad8b7a5af 100644
--- a/chrome/browser/resources/settings/about_page/detailed_build_info.js
+++ b/chrome/browser/resources/settings/about_page/detailed_build_info.js
@@ -18,6 +18,17 @@ Polymer({
 
     /** @private */
     currentlyOnChannelText_: String,
+
+    /** @private */
+    showChannelSwitcherDialog_: Boolean,
+
+    /** @private */
+    canChangeChannel_: {
+      type: Boolean,
+      value: function() {
+        return loadTimeData.getBoolean('aboutCanChangeChannel');
+      },
+    },
   },
 
   /** @override */
@@ -43,4 +54,18 @@ Polymer({
   shouldShowVersion_: function(version) {
     return version.length > 0;
   },
+
+  /** @private */
+  onChangeChannelTap_: function() {
+    this.showChannelSwitcherDialog_ = true;
+    this.async(function() {

[dschuyler, 2016/05/27 22:16:21]

Please add a comment above this.async to
explain why we need to wait.  Maybe:
// Async to wait for dialog to appear in the dom.

[dpapad, 2016/05/27 23:32:18]

Done.

+      var dialog = this.$$('settings-channel-switcher-dialog');
+      // Register listener to detect when the dialog is closed. Flip the boolean
+      // once closed to force a restamp next time it is shown such that the
+      // previous dialog's contents are cleared.
+      dialog.addEventListener('iron-overlay-closed', function() {
+        this.showChannelSwitcherDialog_ = false;
+      }.bind(this));
+    }.bind(this));
+  },
 });