DOMUI: Use a styled button instead of an image for the password list show/hide

chrome/browser/resources/options/search_engine_manager.css

Index: chrome/browser/resources/options/search_engine_manager.css
diff --git a/chrome/browser/resources/options/search_engine_manager.css b/chrome/browser/resources/options/search_engine_manager.css
index 72ef92e4486f2cdba0001deedb347f468ce98f3d..68e3f9b5e140a23473578233a620133a67cf199e 100644
--- a/chrome/browser/resources/options/search_engine_manager.css
+++ b/chrome/browser/resources/options/search_engine_manager.css
@@ -89,21 +89,11 @@
 }
 
 #searchEngineList .url-column button {
-  background-color: #aab6e1;
-  border: none;
-  border-radius: 3px;
-  color: white;
+  background: #8aaaed;
+  color: #fff;
   -webkit-margin-start: 3px;
 }
 
-#searchEngineList .url-column button:hover {
-  background-color: #9aa6d1;
-}
-
-#searchEngineList .url-column button:active {
-  background-color: #8a96c1;
-}
-
 #searchEngineList > :not(:hover):not([editing]) .url-column button {
   display: none;
 }