WebUI MD Refresh: Adjust separator height/margin and button height.

 - Changing button and separator height to 32px.
 - Changing separator margin to 16px.
 - Removing obsolete logic to use a negative margin for non primary buttons.
   It is obsolete since both types of buttons now have a border and they can
   use the same amount of margin.

Bug: 841858,832173
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I1b3bf0d5a7f6b4e81bc5e25a16b422a54487214b
Reviewed-on: https://chromium-review.googlesource.com/1054552Reviewed-by: Scott Chen <scottchen@chromium.org>
Commit-Queue: Demetrios Papadopoulos <dpapad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558075}

chrome/browser/resources/settings/appearance_page/appearance_page.html

@@ -47,10 +47,6 @@
       #themeRow .separator {
          -webkit-margin-start: 0;
       }
-
-      #useSystem {
-        -webkit-margin-start: calc(var(--cr-button-edge-spacing) * -1);
-      }
     </style>
     <settings-animated-pages id="pages" section="appearance"
         focus-config="[[focusConfig_]]">

chrome/browser/resources/settings/controls/controlled_button.html

@@ -15,7 +15,6 @@
       :host {
         --justify-margin: 8px;
         -webkit-margin-end: calc(var(--cr-button-edge-spacing) * -1);
-        -webkit-margin-start: calc(var(--cr-button-edge-spacing) * -1);
         align-items: center;
         display: flex;
       }

chrome/browser/resources/settings/settings_shared_css.html

@@ -88,12 +88,6 @@
         -webkit-margin-start: 16px;
       }
 
-      /* Adjust the margin between the separator and the first button. Exclude
-       * .action-button since it has a background thus is visually different. */
-      .separator + paper-button:not(.action-button) {
-        -webkit-margin-start: calc(var(--cr-button-edge-spacing) * -1);
-      }
-
       span ~ a {
         -webkit-margin-start: 4px;
       }
@@ -325,17 +319,10 @@
        * settings. */
       .separator {
         -webkit-border-start: var(--settings-separator-line);
-        -webkit-margin-end: var(--settings-box-row-padding);
-        -webkit-margin-start: var(--settings-box-row-padding);
         flex-shrink: 0;
-        --settings-separator-gaps: 9px;
-        height: calc(var(--settings-row-min-height) -
-            var(--settings-separator-gaps));
-      }
-
-      .two-line .separator {
-        height: calc(var(--settings-row-two-line-min-height) -
-            2 * var(--settings-separator-gaps));
+        /* Match paper-button's default height. */
+        height: 32px;
+        margin: 0 16px;
       }
 
       .favicon-image {

ui/webui/resources/cr_elements/paper_button_style_css.html

@@ -21,7 +21,7 @@
         color: var(--text-or-bg-color);
         flex-shrink: 0;
         font-weight: 500;
-        height: 36px;
+        height: 32px;
         margin: 0;
         padding: 8px 16px;
         text-decoration: none;