MD Settings: Display > Overscan: Update text and fix focus

chrome/browser/resources/settings/device_page/display_overscan_dialog.js

Index: chrome/browser/resources/settings/device_page/display_overscan_dialog.js
diff --git a/chrome/browser/resources/settings/device_page/display_overscan_dialog.js b/chrome/browser/resources/settings/device_page/display_overscan_dialog.js
index 109301b9c8aad571af0e6ae51c6cadc5e92efa16..e9f245c42c17d4f6faca2abcd21d028620077d5c 100644
--- a/chrome/browser/resources/settings/device_page/display_overscan_dialog.js
+++ b/chrome/browser/resources/settings/device_page/display_overscan_dialog.js
@@ -32,13 +32,17 @@ Polymer({
 
   open: function() {
     this.keyHandler_ = this.handleKeyEvent_.bind(this);
-    this.addEventListener('keydown', this.keyHandler_);
+    // We need to attach the event listener to |window|, not |this| so that
+    // changing focus does not prevent key events from occuring.

[michaelpg, 2016/12/22 07:02:26]

I don't understand the focus bug. Shouldn't tabbing away make the arrow keys
stop affecting the overscan position? Or is the overscan dialog "special"
because of the overlay thingy that happens on-screen?

[stevenjb, 2016/12/22 20:54:14]

The ovescan dialog is "special" because of the overlay thingy that happens
on-screen.

+    window.addEventListener('keydown', this.keyHandler_);
     this.comitted_ = false;
     this.$.dialog.showModal();
+    // Don't focus 'reset' by default. 'Tab' will focus 'OK'.
+    this.$$('#reset').blur();
   },
 
   close: function() {
-    this.removeEventListener('keydown', this.keyHandler_);
+    window.removeEventListener('keydown', this.keyHandler_);
 
     this.displayId = '';  // Will trigger displayIdChanged_.