[Payments] Add the "Cards accepted" row at the top of CC editor.

components/payments/payment_request.h

Index: components/payments/payment_request.h
diff --git a/components/payments/payment_request.h b/components/payments/payment_request.h
index cd54b7cbcebac0e7c0f69c4430af6aa567740a0c..bde059541f4ca2e7bb42e7b1e581beabbe4c8766 100644
--- a/components/payments/payment_request.h
+++ b/components/payments/payment_request.h
@@ -39,7 +39,7 @@ class PaymentRequest : payments::mojom::PaymentRequest {
 
   // payments::mojom::PaymentRequest "stub"
   void Init(payments::mojom::PaymentRequestClientPtr client,
-            std::vector<payments::mojom::PaymentMethodDataPtr> methodData,
+            std::vector<payments::mojom::PaymentMethodDataPtr> method_data,
             payments::mojom::PaymentDetailsPtr details,
             payments::mojom::PaymentOptionsPtr options) override;
   void Show() override;
@@ -101,6 +101,9 @@ class PaymentRequest : payments::mojom::PaymentRequest {
   }
 
   payments::mojom::PaymentDetails* details() { return details_.get(); }
+  const std::vector<std::string>& supported_card_networks() {
+    return supported_card_networks_;
+  }
   content::WebContents* web_contents() { return web_contents_; }
 
  private:
@@ -111,6 +114,10 @@ class PaymentRequest : payments::mojom::PaymentRequest {
   // Sets the default values for the selected Shipping and Contact profiles.
   void SetDefaultProfileSelections();
 
+  // Validates the |method_data| and fills |supported_card_networks_|.
+  void PopulateValidatedMethodData(
+      const std::vector<payments::mojom::PaymentMethodDataPtr>& method_data);
+
   content::WebContents* web_contents_;
   std::unique_ptr<PaymentRequestDelegate> delegate_;
   // |manager_| owns this PaymentRequest.
@@ -119,6 +126,8 @@ class PaymentRequest : payments::mojom::PaymentRequest {
   payments::mojom::PaymentRequestClientPtr client_;
   payments::mojom::PaymentDetailsPtr details_;
   std::unique_ptr<CurrencyFormatter> currency_formatter_;
+  // A set of supported basic card networks.
+  std::vector<std::string> supported_card_networks_;
 
   // Profiles may change due to (e.g.) sync events, so profiles are cached after
   // loading and owned here. They are populated once only, and ordered by