Make the extra padding around VectorIconButtons configurable.

chrome/browser/ui/views/chrome_views_delegate.cc

Index: chrome/browser/ui/views/chrome_views_delegate.cc
diff --git a/chrome/browser/ui/views/chrome_views_delegate.cc b/chrome/browser/ui/views/chrome_views_delegate.cc
index fef73a45e373c2e634787a05d2ac5e7af25fff53..1d64de52ab773d95431ef50614d967ce6483a9ea 100644
--- a/chrome/browser/ui/views/chrome_views_delegate.cc
+++ b/chrome/browser/ui/views/chrome_views_delegate.cc
@@ -250,6 +250,11 @@ int ChromeViewsDelegate::GetButtonHorizontalPadding() const {
       LayoutDelegate::Metric::BUTTON_HORIZONTAL_PADDING);
 }
 
+gfx::Insets ChromeViewsDelegate::GetButtonMargins() const {
+  return gfx::Insets(
+      LayoutDelegate::Get()->GetMetric(LayoutDelegate::Metric::BUTTON_MARGIN));
+}
+
 #if !defined(OS_CHROMEOS)
 views::Widget::InitParams::WindowOpacity
 ChromeViewsDelegate::GetOpacityForInitParams(