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

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

 // Copyright 2017 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/chrome_views_delegate.h"
 #include "chrome/browser/ui/views/harmony/chrome_typography.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/default_style.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/test/material_design_controller_test_api.h"
@@ skipping 191 matching lines @@
   const int twelve = gfx::FontList().GetFontSize() - 1;
 #else
   const int twelve = gfx::FontList().GetFontSize();
 #endif
 
   EXPECT_EQ(twelve, GetFont(CONTEXT_BODY_TEXT_SMALL, kStyle).GetFontSize());
   EXPECT_EQ(twelve, GetFont(views::style::CONTEXT_LABEL, kStyle).GetFontSize());
   EXPECT_EQ(twelve,
             GetFont(views::style::CONTEXT_TEXTFIELD, kStyle).GetFontSize());
   EXPECT_EQ(twelve,
-            GetFont(views::style::CONTEXT_BUTTON, kStyle).GetFontSize());
+            GetFont(views::style::CONTEXT_DIALOG_BUTTON, kStyle).GetFontSize());
 
 #if defined(OS_MACOSX)
   // We never exposed UI on Mac using these constants so it doesn't matter that
   // they are different. They only need to match under Harmony.
   EXPECT_EQ(twelve + 9, GetFont(CONTEXT_HEADLINE, kStyle).GetFontSize());
   EXPECT_EQ(twelve + 2,
             GetFont(views::style::CONTEXT_DIALOG_TITLE, kStyle).GetFontSize());
   EXPECT_EQ(twelve + 2, GetFont(CONTEXT_BODY_TEXT_LARGE, kStyle).GetFontSize());
   EXPECT_EQ(twelve, GetFont(CONTEXT_DEPRECATED_SMALL, kStyle).GetFontSize());
 #else
@@ skipping 36 matching lines @@
     SCOPED_TRACE(testing::Message() << "Testing index: " << i);
     const auto& increase = kExpectedIncreases[i];
     const gfx::FontList& font = views::style::GetFont(increase.context, kStyle);
     int line_spacing = views::style::GetLineHeight(increase.context, kStyle);
     EXPECT_GE(increase.max, line_spacing - font.GetHeight());
     EXPECT_LE(increase.min, line_spacing - font.GetHeight());
   }
 
   // Buttons should specify zero line height (i.e. use the font's height) so
   // buttons have flexibility to configure their own spacing.
-  EXPECT_EQ(0,
-            views::style::GetLineHeight(views::style::CONTEXT_BUTTON, kStyle));
+  EXPECT_EQ(0, views::style::GetLineHeight(views::style::CONTEXT_DIALOG_BUTTON,
+                                           kStyle));
 }