[NTP] Allow image uploads for custom backgrounds

Make the upload an image option in the richer picker work. Selecting
an image and pressing open will immediately close the dialog. This
is consistent with the orgiinal version of the menu but will change
in the future.

Screencast: http://go/scrcast/NTc1MDQ4OTAzMzQ3NDA0OHw1MTNlMmNmMi02Yw

Bug: 937570
Change-Id: I7fa86164d530cc50c60c29385da14b4ae1921878
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1611728
Commit-Queue: Kyle Milka <kmilka@chromium.org>
Reviewed-by: Gayane Petrosyan <gayane@chromium.org>
Cr-Commit-Position: refs/heads/master@{#659742}

chrome/browser/resources/local_ntp/custom_backgrounds.js

@@ -80,6 +80,7 @@ customBackgrounds.IDS = {
   BACKGROUNDS_BUTTON: 'backgrounds-button',
   BACKGROUNDS_IMAGE_MENU: 'backgrounds-image-menu',
   BACKGROUNDS_MENU: 'backgrounds-menu',
+  BACKGROUNDS_UPLOAD: 'backgrounds-upload',
   CANCEL: 'bg-sel-footer-cancel',
   COLORS_BUTTON: 'colors-button',
   CUSTOMIZATION_MENU: 'customization-menu',
@@ -890,7 +891,11 @@ customBackgrounds.loadChromeBackgrounds = function() {
 
 /* Close dialog when an image is selected via the file picker. */
 customBackgrounds.closeCustomizationDialog = function() {
-  $(customBackgrounds.IDS.EDIT_BG_DIALOG).close();
+  if (configData.richerPicker) {
+    $(customBackgrounds.IDS.CUSTOMIZATION_MENU).close();
+  } else {
+    $(customBackgrounds.IDS.EDIT_BG_DIALOG).close();
+  }
 };
 
 /*
@@ -1361,6 +1366,14 @@ customBackgrounds.initCustomBackgrounds = function(showErrorNotification) {
     }
   };
 
+  $(customBackgrounds.IDS.BACKGROUNDS_UPLOAD).onclick = uploadImageInteraction;
+  $(customBackgrounds.IDS.BACKGROUNDS_UPLOAD).onkeydown = function(event) {
+    if (event.keyCode === customBackgrounds.KEYCODES.ENTER ||
+        event.keyCode === customBackgrounds.KEYCODES.SPACE) {
+      uploadImageInteraction();
+    }
+  };
+
   $(customBackgrounds.IDS.BACKGROUNDS_DEFAULT).onclick = function() {
     const tile = $(customBackgrounds.IDS.BACKGROUNDS_DEFAULT_ICON);
     tile.dataset.url = '';