[Payments] Center payment request dialog header

Bug: 840803
Change-Id: I3cf9698c58f8c7e885b16123c05e4a15f8ba53c8
Reviewed-on: https://chromium-review.googlesource.com/1049952Reviewed-by: Mathieu Perreault <mathp@chromium.org>
Commit-Queue: Ganggui Tang <gogerald@chromium.org>
Cr-Commit-Position: refs/heads/master@{#556800}

chrome/browser/ui/views/payments/payment_handler_web_flow_view_controller.cc

@@ -184,7 +184,7 @@ void PaymentHandlerWebFlowViewController::FillContentView(
   // time of first layout (nothing has loaded yet). Because of this, set it to.
   // total_dialog_height - header_height. On the other hand, the width will be
   // properly set so it can be 0 here.
-  web_view->SetPreferredSize(gfx::Size(0, kDialogHeight - 68));
+  web_view->SetPreferredSize(gfx::Size(0, kDialogHeight - 75));
   content_view->AddChildView(web_view.release());
 }
 

chrome/browser/ui/views/payments/payment_request_views_util.cc

@@ -191,12 +191,11 @@ void PopulateSheetHeaderView(bool show_back_arrow,
   views::GridLayout* layout = container->SetLayoutManager(
       std::make_unique<views::GridLayout>(container));
 
-  constexpr int kHeaderTopVerticalInset = 14;
-  constexpr int kHeaderBottomVerticalInset = 8;
+  constexpr int kVerticalInset = 14;
   constexpr int kHeaderHorizontalInset = 16;
-  container->SetBorder(views::CreateEmptyBorder(
-      kHeaderTopVerticalInset, kHeaderHorizontalInset,
-      kHeaderBottomVerticalInset, kHeaderHorizontalInset));
+  container->SetBorder(
+      views::CreateEmptyBorder(kVerticalInset, kHeaderHorizontalInset,
+                               kVerticalInset, kHeaderHorizontalInset));
 
   views::ColumnSet* columns = layout->AddColumnSet(0);
   // A column for the optional back arrow.