[MD Extensions] Add newlines between style rules in HTML

chrome/browser/resources/md_extensions/drop_overlay.html

 <link rel="import" href="chrome://resources/html/cr.html">
 <link rel="import" href="chrome://resources/html/cr/ui/drag_wrapper.html">
 <link rel="import" href="chrome://resources/html/load_time_data.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icons/iron-icons.html">
 <link rel="import" href="chrome://extensions/drag_and_drop_handler.html">
 
 <dom-module id="extensions-drop-overlay">
   <template>
     <style>
       [hidden] {
         display: none !important;
       }
+
       :host {
         align-items: center;
         background-color: white;
         display: flex;
         height: 100%;
         justify-content: center;
         opacity: 0.5;
         position: absolute;
         width: 100%;
         z-index: 10;
       }
+
       #container {
         align-items: center;
         display: flex;
         flex-direction: column;
       }
+
       iron-icon {
         color: var(--paper-teal-a400);
         height: 64px;
         width: 64px;
       }
     </style>
     <div id="container">
       <iron-icon icon="extension"></iron-icon>
       <div>$i18n{dropToInstall}</div>
     </div>
   </template>
   <script src="chrome://extensions/drop_overlay.js"></script>
 </dom-module>