Remove LegacyChromeFeatureList.

It is now unused. This was a transitory class to move downstream
references to ChromeFeatureList without causing breakages.

This is CL 5/5 for moving ChromeFeatureList to the .flags package.

Bug: 1041468
Change-Id: Iab7b13219bbd9b808c53f23e40d5e5b064ba20f5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2003450Reviewed-by: Theresa  <twellington@chromium.org>
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#733617}

chrome/android/chrome_java_sources.gni

@@ -43,7 +43,6 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/KeyboardShortcuts.java",
   "java/src/org/chromium/chrome/browser/LaunchIntentDispatcher.java",
   "java/src/org/chromium/chrome/browser/LauncherShortcutActivity.java",
-  "java/src/org/chromium/chrome/browser/LegacyChromeFeatureList.java",
   "java/src/org/chromium/chrome/browser/MenuOrKeyboardActionController.java",
   "java/src/org/chromium/chrome/browser/NavigationPopup.java",
   "java/src/org/chromium/chrome/browser/NearOomMonitor.java",

chrome/android/java/src/org/chromium/chrome/browser/LegacyChromeFeatureList.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;
-
-import org.chromium.chrome.browser.flags.ChromeFeatureList;
-
-/**
- * Temporary class, identical to {@link ChromeFeatureList}, for migration.
- *
- * This class will be referenced temporarily while ChromeFeatureList is moved to the .flags
- * package.
- *
- * TODO(crbug.com/1041468): Remove this class after downstream uses flags.ChromeFeatureList.
- */
-public abstract class LegacyChromeFeatureList extends ChromeFeatureList {
-}

chrome/android/java/src/org/chromium/chrome/browser/flags/ChromeFeatureList.java

@@ -23,7 +23,7 @@ public abstract class ChromeFeatureList {
     private static Map<String, Boolean> sTestFeatures;
 
     // Prevent instantiation.
-    protected ChromeFeatureList() {}
+    private ChromeFeatureList() {}
 
     /**
      * Sets the feature flags to use in JUnit tests, since native calls are not available there.