Remove ::shadow and /deep/ combinator from Files app.

ui/file_manager/gallery/css/gallery.css

Index: ui/file_manager/gallery/css/gallery.css
diff --git a/ui/file_manager/gallery/css/gallery.css b/ui/file_manager/gallery/css/gallery.css
index e655980fa222e1b2a65169c732cfed01ef9b63f6..1db0ed047f1a7c7a647e29880c68a9863fe873fd 100644
--- a/ui/file_manager/gallery/css/gallery.css
+++ b/ui/file_manager/gallery/css/gallery.css
@@ -76,15 +76,10 @@ html[dir='rtl'] .bubble .close-x {
   opacity: 0.7;
 }
 
-paper-ripple,
-paper-button::shadow paper-ripple {
+paper-ripple {
   color: black;
 }
 
-files-toggle-ripple::shadow .ripple.activated {
-  opacity: 0.4;
-}
-
 .gallery,
 .gallery > .content {
   bottom: 0;
@@ -556,8 +551,7 @@ html[dir='rtl'] .gallery .toolbar .bubble {
   -webkit-margin-start: 16px;
 }
 
-.edit-mode-toolbar .overwrite-original[disabled]::shadow #checkbox,
-.edit-mode-toolbar .overwrite-original[disabled]::shadow #checkboxLabel {
+.edit-mode-toolbar .overwrite-original[disabled] {
   opacity: 0.2;
 }
 
@@ -915,10 +909,6 @@ paper-slider {
   width: 172px;
 }
 
-paper-slider::shadow paper-progress::shadow #progressContainer {
-  background-color: rgba(255, 255, 255, 0.2);
-}
-
 .edit-modal .range.brightness > .icon {
   background-image: -webkit-image-set(
       url(../images/100/brightness.png) 1x,