Implement Harmony-style consistent button widths for Collected Cookies.

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

Index: chrome/browser/ui/views/harmony/layout_delegate.cc
diff --git a/chrome/browser/ui/views/harmony/layout_delegate.cc b/chrome/browser/ui/views/harmony/layout_delegate.cc
index d366297d1520fffbeb0db5a3fd029cdd8165bb85..273d537a54537381c92f920c4e5a5f8317e1b5f2 100644
--- a/chrome/browser/ui/views/harmony/layout_delegate.cc
+++ b/chrome/browser/ui/views/harmony/layout_delegate.cc
@@ -52,6 +52,8 @@ int LayoutDelegate::GetMetric(Metric metric) const {
       return views::kUnrelatedControlVerticalSpacing;
     case Metric::UNRELATED_CONTROL_VERTICAL_SPACING_LARGE:
       return views::kUnrelatedControlLargeVerticalSpacing;
+    case Metric::BUTTON_MAX_SHARED_WIDTH:
+      return 0;  // Buttons never expand during layout (add padding instead).
   }
   NOTREACHED();
   return 0;