Implement ChromeViewsDelegate methods in terms of LayoutDelegate where possible.

chrome/browser/ui/views/chrome_views_delegate.h

Index: chrome/browser/ui/views/chrome_views_delegate.h
diff --git a/chrome/browser/ui/views/chrome_views_delegate.h b/chrome/browser/ui/views/chrome_views_delegate.h
index 646d2f56bf19b5422882ac74e1c42788fe0b1025..d860f71ec52c4d26101da08e4e07e48802b27abc 100644
--- a/chrome/browser/ui/views/chrome_views_delegate.h
+++ b/chrome/browser/ui/views/chrome_views_delegate.h
@@ -62,11 +62,11 @@ class ChromeViewsDelegate : public views::ViewsDelegate {
 #endif
   scoped_refptr<base::TaskRunner> GetBlockingPoolTaskRunner() override;
 
-  gfx::Insets GetDialogButtonInsets() override;
-  int GetDialogRelatedButtonHorizontalSpacing() override;
-  int GetDialogRelatedControlVerticalSpacing() override;
-  gfx::Insets GetDialogFrameViewInsets() override;
-  gfx::Insets GetBubbleDialogMargins() override;
+  gfx::Insets GetDialogButtonInsets() const override;
+  int GetDialogRelatedButtonHorizontalSpacing() const override;
+  int GetDialogRelatedControlVerticalSpacing() const override;
+  gfx::Insets GetDialogFrameViewInsets() const override;
+  gfx::Insets GetBubbleDialogMargins() const override;
 
  private:
 #if defined(OS_WIN)