MD Settings: prevent input labels from shifting around.

chrome/browser/resources/settings/settings_vars_css.html

 <link rel="import" href="chrome://resources/cr_elements/shared_vars_css.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-styles/color.html">
 
 <!-- Common css variables for Material Design settings. -->
 <style is="custom-style">
   /* We keep our vars in sort order, though some vars must be defined prior to
    * others. The --settings-* vars are defined explicitly prior to the --paper-*
    * and --iron-* vars.
    */
   :root {
@@ skipping 79 matching lines @@
 
     --cr-icon-ripple-size: 40px;
     --paper-icon-button: {
       /**
        * This makes the icons 20px (in combination with "--cr-icon-ripple-size:
        * 40px"), since paper-icon-button>iron-icon width and height are
        * hardcoded to 100%.
        */
       padding: 10px;
     };
+    --paper-input-container: {
+      transform: translate3d(0, 0, 0);

[dpapad, 2017/04/14 22:50:07]

Let's add a short comment here.

+    };
     --paper-input-container-focus-color: var(--google-blue-500);
     --paper-input-container-input: {
       color: inherit;
       font-size: inherit;
       font-weight: inherit;
       line-height: 154%;
       vertical-align: baseline;
     };
     --paper-input-container-label: {
       font-size: inherit;
@@ skipping 27 matching lines @@
     --paper-toggle-button-unchecked-button: var(--settings-toggle-button-size);
     --paper-toggle-button-unchecked-ink: var(--settings-toggle-ink-size);
 
     --settings-input-underline: {
       border-color: var(--paper-grey-300);
     };
 
     --paper-input-container-underline: var(--settings-input-underline);
   }
 </style>