[WebPayments] Disabling done button when form invalid

chrome/browser/ui/views/payments/editor_view_controller.h

Index: chrome/browser/ui/views/payments/editor_view_controller.h
diff --git a/chrome/browser/ui/views/payments/editor_view_controller.h b/chrome/browser/ui/views/payments/editor_view_controller.h
index 216b45cb3880a3c0cfbdc62a6014ed59339b4719..81110c057fab367205aaf4d1799b09eea4c11164 100644
--- a/chrome/browser/ui/views/payments/editor_view_controller.h
+++ b/chrome/browser/ui/views/payments/editor_view_controller.h
@@ -129,6 +129,7 @@ class EditorViewController : public PaymentRequestSheetController,
       autofill::ServerFieldType type) = 0;
   // Validates the data entered and attempts to save; returns true on success.
   virtual bool ValidateModelAndSave() = 0;
+
   // Creates a ValidationDelegate which knows how to validate for a given
   // |field| definition.
   virtual std::unique_ptr<ValidationDelegate> CreateValidationDelegate(
@@ -136,6 +137,11 @@ class EditorViewController : public PaymentRequestSheetController,
   virtual std::unique_ptr<ui::ComboboxModel> GetComboboxModelForType(
       const autofill::ServerFieldType& type) = 0;
 
+  // Returns true if all fields are valid. Relies on cached validity values,

[Mathieu, 2017/05/29 16:45:36]

no cache?

[tmartino, 2017/05/29 21:06:58]

Done

+  // which are computed once for all fields at init-time, and subsequently
+  // upon user interactions on a per-field basis.
+  bool ValidateModel();
+
   // PaymentRequestSheetController;
   std::unique_ptr<views::Button> CreatePrimaryButton() override;
   void FillContentView(views::View* content_view) override;