Add icon-visibility attribute to cr.ui.Tree.

chrome/browser/resources/shared/css/tree.css

Index: chrome/browser/resources/shared/css/tree.css
diff --git a/chrome/browser/resources/shared/css/tree.css b/chrome/browser/resources/shared/css/tree.css
index ac0b1de29f7d746c93c3a4026483f5f4403396ce..3b29f1a683d0b74d76c0efea26fa1ce6ce39b83c 100644
--- a/chrome/browser/resources/shared/css/tree.css
+++ b/chrome/browser/resources/shared/css/tree.css
@@ -100,40 +100,55 @@ tree:focus .tree-row[selected] {
 
 .tree-label {
   -webkit-padding-start: 20px;
-  background-image: url("../../../../../ui/resources/folder_closed.png");
   background-position: 0 50%;
   background-repeat: no-repeat;
   white-space: pre;
 }
 
-/* We need to ensure that even empty labels take up space */
-.tree-label:empty:after {
-  content: " ";
-  white-space: pre;
+html[dir=rtl] .tree-label {
+  background-position: 100% 50%;
 }
 
-.tree-rename > .tree-row > .tree-label {
-  -webkit-user-select: auto;
-  -webkit-user-modify: read-write-plaintext-only;
-  background: white;
-  color: black;
-  outline: 1px solid black;
+html[dir=rtl] .tree-label,
+html[dir=rtl] .tree-row[may-have-children] > .tree-label {
+  background-image: url("../../../../../ui/resources/folder_closed_rtl.png");
 }
 
-html[dir=rtl] .tree-label {
-  background-position: 100% 50%;
+html[dir=rtl] .tree-item[expanded] > .tree-row > .tree-label {
+  background-image: url("../../../../../ui/resources/folder_open_rtl.png");
+}
+
+tree[icon-visibility=hidden] .tree-label {
+  -webkit-padding-start: 0;
+  background-image: none !important;
+}
+
+tree[icon-visibility=parent] .tree-label,
+tree[icon-visibility=parent] .tree-row[has-children=false] > .tree-label {
+  background-image: none;
+}
+
+.tree-label,
+.tree-row[may-have-children] > .tree-label {
+  background-image: url("../../../../../ui/resources/folder_closed.png");
 }
 
 .tree-item[expanded] > .tree-row > .tree-label {
   background-image: url("../../../../../ui/resources/folder_open.png");
 }
 
-html[dir='rtl'] .tree-label {
-  background-image: url("../../../../../ui/resources/folder_closed_rtl.png");
+/* We need to ensure that even empty labels take up space */
+.tree-label:empty:after {
+  content: " ";
+  white-space: pre;
 }
 
-html[dir='rtl'] .tree-item[expanded] > .tree-row > .tree-label {
-  background-image: url("../../../../../ui/resources/folder_open_rtl.png");
+.tree-rename > .tree-row > .tree-label {
+  -webkit-user-select: auto;
+  -webkit-user-modify: read-write-plaintext-only;
+  background: white;
+  color: black;
+  outline: 1px solid black;
 }
 
 .tree-item[editing] input {