md settings: Small changes to lock screen.

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

Index: chrome/browser/resources/settings/people_page/password_prompt_dialog.js
diff --git a/chrome/browser/resources/settings/people_page/password_prompt_dialog.js b/chrome/browser/resources/settings/people_page/password_prompt_dialog.js
index 96be633de90375b467f384779894df24812373fa..b234939aadc466d9ace73794e146106f38f21638 100644
--- a/chrome/browser/resources/settings/people_page/password_prompt_dialog.js
+++ b/chrome/browser/resources/settings/people_page/password_prompt_dialog.js
@@ -110,6 +110,9 @@ Polymer({
 
     this.writeUma_(LockScreenProgress.START_SCREEN_LOCK);
     this.$.dialog.showModal();
+    this.async(function() {
+      this.$.passwordInput.shadowRoot.querySelector('#input').focus();

[sammiequon, 2017/04/14 17:22:07]

This is kind of messy but the JS guide doesn't allow
this.$.passwordInput.$.input.focus(); and this.$.passwordInput.focus() doesn't
do the job.

[stevenjb, 2017/04/14 21:47:20]

If this.$.passwordInput.focus() doesn't work that sounds like a bug.

dpapad@ - Do you know anything about that?

[stevenjb, 2017/04/14 21:51:30]

Oh, actually, I think your problem may be that this.$.foo doesn't work when
|foo| is inside a <template>, maybe <dialog> has the same problem. Try this
instead:

this.$$('#passwordInput').focus();

Also, I don't think you need the async() since the dialog is not templated out.

[sammiequon, 2017/04/14 22:11:43]

That doesn't seem to work, it has the same behaviour as
this.$.passwordInput.focus() in that the focus is there the first time but
consequent opens of this dialog the focus is missing. It also does not work
without async.

[stevenjb, 2017/04/14 22:29:02]

Hmm, I think we need to investigate that then. Querying the shadowRoot like this
is not something we want to be doing.

[sammiequon, 2017/04/14 23:48:13]

Acknowledged. Let me see if I can find a better approach.

+    }.bind(this));
   },
 
   /** @private */