chromeos: Update OS settings drawer title style to spec

OS settings uses G Grey 700, weight 500, different spacing, and no
border under the title.

http://screen/61xziJEyQqx

Bug: 994790
Change-Id: I71346581fcfb66da3a773f89c664544393472625
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1761066
Commit-Queue: James Cook <jamescook@chromium.org>
Reviewed-by: Hector Carmona <hcarmona@chromium.org>
Cr-Commit-Position: refs/heads/master@{#688346}

chrome/browser/resources/settings/chromeos/os_settings_ui/os_settings_ui.html

@@ -49,6 +49,13 @@
         --cr-toolbar-search-field-input-color: var(--google-grey-refresh-700);
       }
 
+      cr-drawer {
+        --cr-separator-line: none;
+        --cr-drawer-header-color: var(--google-grey-refresh-700);
+        --cr-drawer-header-font-weight: 500;
+        --cr-drawer-header-padding: 20px;
+      }
+
       #cr-container-shadow-top {
         /* Needs to be higher than #container's z-index to appear above
          * scrollbars. */

ui/webui/resources/cr_elements/cr_drawer/cr_drawer.html

@@ -68,11 +68,13 @@
       .drawer-header {
         align-items: center;
         border-bottom: var(--cr-separator-line);
+        color: var(--cr-drawer-header-color, inherit);
         display: flex;
         font-size: 123.08%;  /* go to 16px from 13px */
+        font-weight: var(--cr-drawer-header-font-weight, inherit);
         min-height: 56px;
         outline: none;
-        padding-inline-start: 24px;
+        padding-inline-start: var(--cr-drawer-header-padding, 24px);
       }
 
       @media (prefers-color-scheme: dark) {