Remove unused images and CSS properties.

ui/file_manager/file_manager/foreground/css/common.css

Index: ui/file_manager/file_manager/foreground/css/common.css
diff --git a/ui/file_manager/file_manager/foreground/css/common.css b/ui/file_manager/file_manager/foreground/css/common.css
index 868fa9403dc412021e065db98c0012869977144d..6b14673219d71d12a85758fc7c570a063891226e 100644
--- a/ui/file_manager/file_manager/foreground/css/common.css
+++ b/ui/file_manager/file_manager/foreground/css/common.css
@@ -7,114 +7,6 @@
   display: none !important;
 }
 
-/* This file contains "borrowed" copy of standard styles. To simplify merging,
- * when altering, please preserve original property value by adding comments. */
-input.common[type='checkbox'],
-input.common[type='radio'] {
-  -webkit-appearance: none;
-  border: 1px solid #555;
-  border-radius: 1px;
-  box-sizing: border-box;
-  cursor: default;
-  height: 13px;
-  margin: 0;
-  opacity: 0.4;
-  width: 13px;
-}
-
-input.common[type='checkbox']:hover,
-input.common[type='checkbox']:checked,
-input.common[type='radio']:hover,
-input.common[type='radio']:checked {
-  opacity: 1;
-}
-
-input.common[type='checkbox'] {
-  position: relative;
-}
-
-input.common[type='checkbox']:checked::after {
-  background-image: -webkit-image-set(
-    url(../images/common/check_no_box.png) 1x,
-    url(../images/common/2x/check_no_box.png) 2x);
-  background-position: -3px -4px;
-  background-repeat: no-repeat;
-}
-
-input.common[type='checkbox'].white {
-  border: none;
-}
-
-input.common[type='checkbox'].white:not(:checked)::after {
-  background-image: -webkit-image-set(
-    url(../images/common/checkbox_white_unchecked.png) 1x,
-    url(../images/common/2x/checkbox_white_unchecked.png) 2x);
-  background-position: -1px 0;
-}
-
-input.common[type='checkbox'].white:checked::after {
-  background-image: -webkit-image-set(
-    url(../images/common/checkbox_white_checked.png) 1x,
-    url(../images/common/2x/checkbox_white_checked.png) 2x);
-  background-position: -1px 0;
-}
-
-input.common[type='checkbox']::after {
-  content: '';
-  display: flex;
-  height: 15px;
-  left: -2px;
-  position: absolute;
-  top: -2px;
-  width: 17px;
-}
-
-.bubble {
-  background: #FFF;
-  border-radius: 2px;
-  cursor: default;
-  outline: 1px solid rgba(0, 0, 0, 0.2);
-  padding: 16px;
-}
-
-.bubble .pointer {
-  background: -webkit-image-set(
-    url(../images/common/bubble_point_white.png) 1x,
-    url(../images/common/2x/bubble_point_white.png) 2x);
-  display: block;
-  height: 11px;
-  left: 24px;
-  margin: 0 0 0 -5px;
-  outline: none;
-  position: absolute;
-  width: 17px;
-}
-
-.bubble .pointer:not(.bottom) {
-  top: -11px;
-}
-
-.bubble .pointer.bottom {
-  -webkit-transform: rotate(180deg);
-  bottom: -11px;
-}
-
-.bubble .close-x {
-  background: -webkit-image-set(
-    url(../images/common/close_x_gray.png) 1x,
-    url(../images/common/2x/close_x_gray.png) 2x);
-  height: 21px;
-  opacity: 0.3;
-  position: absolute;
-  right: 3px;
-  top: 3px;
-  width: 21px;
-}
-
-.bubble .close-x:hover {
-  opacity: 0.7;
-}
-
 /* "chrome-menu" class overrides some standard menu.css styles, to make custom
    menus in FileBrowser look like native ChromeOS menus. */