[Passwords] Add interface definition for a Touch To Fill View

This change adds the interface definition for a Touch To Fill View which
will is intended to be implemented on Android in a follow-up CL.

Bug: 957532
Change-Id: I819e8178db21c32d577560da82c64d79856a59cb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1798356
Commit-Queue: Jan Wilken Dörrie <jdoerrie@chromium.org>
Reviewed-by: Friedrich [CET] <fhorschig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#695749}

chrome/browser/BUILD.gn

@@ -2842,6 +2842,7 @@ jumbo_split_static_library("browser") {
       "password_manager/save_password_infobar_delegate_android.h",
       "password_manager/touch_to_fill_controller.cc",
       "password_manager/touch_to_fill_controller.h",
+      "password_manager/touch_to_fill_view.h",
       "password_manager/update_password_infobar_delegate_android.cc",
       "password_manager/update_password_infobar_delegate_android.h",
       "payments/android/can_make_payment_query_android.cc",

chrome/browser/password_manager/touch_to_fill_view.h

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_PASSWORD_MANAGER_TOUCH_TO_FILL_VIEW_H_
+#define CHROME_BROWSER_PASSWORD_MANAGER_TOUCH_TO_FILL_VIEW_H_
+
+#include "base/callback_forward.h"
+#include "base/containers/span.h"
+#include "base/strings/string_piece_forward.h"
+
+namespace password_manager {
+struct CredentialPair;
+}
+
+// This class represents the interface used for communicating between the Touch
+// To Fill controller with the Android frontend.
+class TouchToFillView {
+ public:
+  using ShowCallback =
+      base::OnceCallback<void(const password_manager::CredentialPair&)>;
+
+  TouchToFillView() = default;
+  TouchToFillView(const TouchToFillView&) = delete;
+  TouchToFillView& operator=(const TouchToFillView&) = delete;
+  virtual ~TouchToFillView() = default;
+
+  // Instructs Touch To Fill to show the provided |credentials| to the user.
+  // |formatted_url| contains a human friendly version of the current origin.
+  // Invokes |callback| once the user chose a credential.
+  virtual void Show(
+      base::StringPiece16 formatted_url,
+      base::span<const password_manager::CredentialPair> credentials,
+      ShowCallback callback) = 0;
+
+  // Invoked if the user dismissed the Touch To Fill sheet without choosing a
+  // credential.
+  virtual void OnDismiss() = 0;
+};
+
+#endif  // CHROME_BROWSER_PASSWORD_MANAGER_TOUCH_TO_FILL_VIEW_H_