Gallery.app: make edit button toggleable.

ui/file_manager/gallery/css/gallery.css

 /* Copyright (c) 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. */
 
 body {
   -webkit-user-select: none;
   font-size: 84%;
   margin: 0;
 }
 
@@ skipping 556 matching lines @@
   overflow: visible;
 }
 
 .gallery[editing] .edit-bar-spacer {
   opacity: 1.0;
   pointer-events: auto;
   transition-delay: 100ms, 100ms;
   visibility: visible;
 }
 
-.gallery > .toolbar paper-button {
+.gallery > .toolbar paper-button,
+.gallery > .toolbar button {
   background-position: center;
   background-repeat: no-repeat;
   height: 32px;
   margin: 0 8px;
   min-width: 32px;
   width: 32px;
 }
 
+.gallery > .toolbar button {
+  background-color: transparent;
+  border: 0;
+  padding: 0;
+  position: relative;
+}
+
+.gallery > .toolbar button > .icon {
+  background-position: center;
+  background-repeat: no-repeat;
+  height: 100%;
+  position: relative;
+  width: 100%;
+  z-index: 2;
+}
+
+.gallery > .toolbar button > files-toggle-ripple {
+  position: absolute;
+  top: 0;
+  z-index: 1;
+}
+
 .gallery > .toolbar paper-button:focus {
   background-color: rgba(0, 0, 0, 0.3);
 }
 
-.gallery > .toolbar paper-button.edit {
+.gallery > .toolbar button.edit > .icon {
   background-image: -webkit-image-set(
       url(../images/100/edit.png) 1x,
       url(../images/200/edit.png) 2x);
 }
 
 .gallery > .toolbar paper-button.print {
   background-image: -webkit-image-set(
       url(../images/100/print.png) 1x,
       url(../images/200/print.png) 2x);
 }
@@ skipping 26 matching lines @@
   background-image: -webkit-image-set(
       url(../images/100/share.png) 1x,
       url(../images/200/share.png) 2x);
 }
 
 .gallery[editing] > .toolbar paper-button.edit {
   opacity: 0.5;
   pointer-events: none;
 }
 
-.gallery:not([editing])[mode='slide'] > .toolbar .button.slide-mode,
-.gallery:not([editing])[mode='thumbnail'] > .toolbar .button.thumbnail-mode,
-.gallery[editing][mode='slide'] > .toolbar .button.thumbnail-mode,
-.gallery > .toolbar paper-button[disabled] {
+.gallery:not([editing])[mode='slide'] > paper-button.slide-mode,
+.gallery:not([editing])[mode='thumbnail'] > paper-button.thumbnail-mode,
+.gallery[editing][mode='slide'] > paper-button.thumbnail-mode,
+paper-button[disabled],
+button[disabled] {
   display: none;
 }
 
 /* Button in edit toolbar. */
 button.edit-toolbar,
 button.edit-toolbar[disabled] {
   background-color: rgba(0, 0, 0, 0);
   background-position: center;
   background-repeat: no-repeat;
   border: none;
@@ skipping 771 matching lines @@
 .thumbnail-view .animation-thumbnail {
   background-repeat: no-repeat;
   background-size: cover;
   display: none;
   position: absolute;
 }
 
 .thumbnail-view .animation-thumbnail.animating {
   display: block;
 }