Update bookmark bar folder icons to MD; vectorize.

ui/gfx/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
@@ skipping 416 matching lines @@
     "vector_icons/cookie.icon",
     "vector_icons/extension.icon",
     "vector_icons/file_download.icon",
     "vector_icons/file_download_shelf.icon",
     "vector_icons/find_close.1x.icon",
     "vector_icons/find_close.icon",
     "vector_icons/find_next.1x.icon",
     "vector_icons/find_next.icon",
     "vector_icons/find_prev.1x.icon",
     "vector_icons/find_prev.icon",
+    "vector_icons/folder.icon",
+    "vector_icons/folder_managed.icon",
+    "vector_icons/folder_supervised.icon",
     "vector_icons/fullscreen.icon",
     "vector_icons/help_outline.icon",
     "vector_icons/image.icon",
     "vector_icons/laptop.icon",
     "vector_icons/location_on.icon",
     "vector_icons/midi.icon",
     "vector_icons/mixed_content.icon",
     "vector_icons/mode_edit.icon",
     "vector_icons/my_location.icon",
     "vector_icons/notifications.icon",
@@ skipping 221 matching lines @@
 if (is_android) {
   generate_jni("gfx_jni_headers") {
     sources = [
       "../android/java/src/org/chromium/ui/gfx/BitmapHelper.java",
       "../android/java/src/org/chromium/ui/gfx/DeviceDisplayInfo.java",
       "../android/java/src/org/chromium/ui/gfx/ViewConfigurationHelper.java",
     ]
     jni_package = "gfx"
   }
 }