Use views::style for buttons, bootstrap ash_typography to do so.

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

Index: chrome/browser/ui/views/harmony/harmony_typography_provider.cc
diff --git a/chrome/browser/ui/views/harmony/harmony_typography_provider.cc b/chrome/browser/ui/views/harmony/harmony_typography_provider.cc
index 21caf0cb832f7db4b16030d0338632a8d7852927..65a428f8101b214eed07633e1590dcc7b12dc6c1 100644
--- a/chrome/browser/ui/views/harmony/harmony_typography_provider.cc
+++ b/chrome/browser/ui/views/harmony/harmony_typography_provider.cc
@@ -8,6 +8,10 @@
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/platform_font.h"
 
+#if defined(USE_ASH)
+#include "ash/common/ash_typography.h"
+#endif
+
 const gfx::FontList& HarmonyTypographyProvider::GetFont(int text_context,
                                                         int text_style) const {
   // "Target" font size constants from the Harmony spec.
@@ -34,14 +38,19 @@ const gfx::FontList& HarmonyTypographyProvider::GetFont(int text_context,
     case CONTEXT_BODY_TEXT_LARGE:
       size_delta = kBodyTextLargeSize - gfx::PlatformFont::kDefaultBaseFontSize;
       break;
-    case views::style::CONTEXT_BUTTON:
-      font_weight = kButtonFontWeight;
+    case views::style::CONTEXT_BUTTON_MD:
+      font_weight = WeightNotLighterThanNormal(kButtonFontWeight);
       break;
     default:
       break;
   }
 
   // Ignore |text_style| since it only affects color in the Harmony spec.
+
+#if defined(USE_ASH)
+  ash::GetDefaultAshFont(text_context, text_style, &size_delta, &font_weight);

[Peter Kasting, 2017/04/08 01:38:54]

Nit: I liked doing this above the switch, as you did in chrome_typography.cc,
better

[tapted, 2017/04/10 12:27:33]

Done.

+#endif
+
   return ui::ResourceBundle::GetSharedInstance().GetFontListWithDelta(
       size_delta, gfx::Font::NORMAL, font_weight);
 }