[Web Payment] Remove PaymentInstrument.java class.

The PaymentInstrument.java class is an empty wrapper around
PaymentApp.java. All dependencies on PaymentInstrument.java have been
updated to use the PaymentApp.java class instead.

Bug: 1022512
Change-Id: Ia79bdca2bc98c33c6e1921336950c8e25dc500b6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2087976Reviewed-by: Sahel Sharify <sahel@chromium.org>
Commit-Queue: Rouslan Solomakhin <rouslan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#747277}

chrome/android/chrome_java_sources.gni

@@ -1266,7 +1266,6 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/payments/PaymentAppFactoryInterface.java",
   "java/src/org/chromium/chrome/browser/payments/PaymentAppFactoryParams.java",
   "java/src/org/chromium/chrome/browser/payments/PaymentAppService.java",
-  "java/src/org/chromium/chrome/browser/payments/PaymentInstrument.java",
   "java/src/org/chromium/chrome/browser/payments/PaymentManifestVerifier.java",
   "java/src/org/chromium/chrome/browser/payments/PaymentManifestWebDataService.java",
   "java/src/org/chromium/chrome/browser/payments/PaymentPreferencesUtil.java",

chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentInstrument.java

-// Copyright 2020 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.
-
-package org.chromium.chrome.browser.payments;
-
-import android.graphics.drawable.Drawable;
-
-/** Stub. TODO(rouslan): Remove this file. */
-public abstract class PaymentInstrument extends PaymentApp {
-    protected PaymentInstrument(String id, String label, String sublabel, Drawable icon) {
-        super(id, label, sublabel, icon);
-    }
-
-    protected PaymentInstrument(
-            String id, String label, String sublabel, String tertiarylabel, Drawable icon) {
-        super(id, label, sublabel, tertiarylabel, icon);
-    }
-}