Settings People Revamp: Simplify Change Picture browsertests.

chrome/browser/resources/settings/people_page/change_picture.js

Index: chrome/browser/resources/settings/people_page/change_picture.js
diff --git a/chrome/browser/resources/settings/people_page/change_picture.js b/chrome/browser/resources/settings/people_page/change_picture.js
index 57d0e24f8b57914b868ba88a94f4ff80f6171e96..ff7ce41438f0aa9594dba27e1d8ab30920e4a139 100644
--- a/chrome/browser/resources/settings/people_page/change_picture.js
+++ b/chrome/browser/resources/settings/people_page/change_picture.js
@@ -49,7 +49,7 @@ Polymer({
      */
     selectedItem_: {

[dpapad, 2016/04/09 00:16:35]

Shouldn't this be

 /**
  * @private {settings.ChangePictureImageElement}
  */
 selectedItem_: Object,


I don't think you can use the typedef name as the "type" value in a Polymer
property, only Boolean, Date, Number, String, Array or Object is accepted.

[tommycli, 2016/04/11 19:09:57]

Done. Yes I think you are correct. I wonder what is actually happening when I do
this.

       type: settings.ChangePictureImageElement,
-      notify: !!settings_test.changePictureNotifyForTest,
+      value: null,
     },
 
     /**
@@ -322,8 +322,7 @@ Polymer({
     assert(this.defaultImages_.length > 0);
     this.browserProxy_.selectDefaultImage(this.defaultImages_[0].url);
 
-    announceAccessibleMessage(
-        loadTimeData.getString('photoDiscardAccessibleText'));
+    announceAccessibleMessage(this.i18n('photoDiscardAccessibleText'));
   },
 
   /**
@@ -353,7 +352,7 @@ Polymer({
    * @private
    */
   isCameraActive_: function(cameraPresent, selectedItem) {
-    return cameraPresent && selectedItem &&
+    return cameraPresent && selectedItem != null &&

[dpapad, 2016/04/09 00:16:35]

Nit (optional): Use "!==" instead of "!=".

[tommycli, 2016/04/11 19:09:57]

This didn't work for me because even with the value: null, the value is
momentarily undefined when the page is first loaded. Not sure why.

[dpapad, 2016/04/11 19:36:38]

That is odd. Polymer data bindings guarantee that this function will not be
called until all dependencies (cameraPresent and selectedItem) are set to a
non-undefined value, pasting below from the docs:

"The computing function is not called until all dependent properties are defined
(!=undefined)."

I am fine with leaving as is, but it would be nice to understand why does the
behavior not match the Polymer docs. I have definitely seen the advertized
behavior working in other cases.

[tommycli, 2016/04/11 21:20:52]

I investigated this in detail. Basically: when iron-selector selects a different
item, the selectedItem momentarily becomes undefined, and then it becomes
defined again (to the new item).

I filed an issue: https://github.com/PolymerElements/iron-selector/issues/118

In the meantime i will leave these computed bindings as 'falsy'.

[dpapad, 2016/04/11 21:29:33]

Thanks for investigating!

         selectedItem.dataset.type == 'camera';
   },
 
@@ -372,7 +371,7 @@ Polymer({
    * @private
    */
   isAuthorCreditShown_: function(selectedItem) {
-    return selectedItem && selectedItem.dataset.type == 'default';
+    return selectedItem != null && selectedItem.dataset.type == 'default';
   },
 
   /**