Make the extra padding around VectorIconButtons configurable.

chrome/browser/ui/views/harmony/layout_delegate.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/views/harmony/layout_delegate.h"
 
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "chrome/browser/ui/views/harmony/harmony_layout_delegate.h"
 #include "ui/base/material_design/material_design_controller.h"
 #include "ui/views/layout/layout_constants.h"
 
 static base::LazyInstance<LayoutDelegate> layout_delegate_ =
     LAZY_INSTANCE_INITIALIZER;
 
 // static
 LayoutDelegate* LayoutDelegate::Get() {
   return ui::MaterialDesignController::IsSecondaryUiMaterial()
              ? HarmonyLayoutDelegate::Get()
              : layout_delegate_.Pointer();
 }
 
 int LayoutDelegate::GetMetric(Metric metric) const {
   switch (metric) {
     case Metric::BUTTON_HORIZONTAL_PADDING:
       return views::kButtonHorizontalPadding;
+    case Metric::BUTTON_MARGIN:
+      return views::kButtonExtraTouchSize;
     case Metric::BUTTON_MINIMUM_WIDTH:
       return views::kMinimumButtonWidth;
     case Metric::DIALOG_BUTTON_MARGIN:
       return views::kButtonHEdgeMarginNew;
     case Metric::DIALOG_BUTTON_MINIMUM_WIDTH:
       return views::kDialogMinimumButtonWidth;
     case Metric::DIALOG_BUTTON_TOP_SPACING:
       return 0;
     case Metric::DIALOG_CLOSE_BUTTON_MARGIN:
       return views::kCloseButtonMargin;
@@ skipping 31 matching lines @@
   return true;
 }
 
 bool LayoutDelegate::IsHarmonyMode() const {
   return false;
 }
 
 int LayoutDelegate::GetDialogPreferredWidth(DialogWidth width) const {
   return 0;
 }