Remove deprecated class WebContentsObserverAndroid and cleanup existing usages.

In continuation of the CL https://codereview.chromium.org/589113002/
this CL removes deprecated class WebContentsObserverAndroid and
cleans up existing usage of this class where ever it is occured.

This patch will be landed when external repositories has renamed
WebContentsObserverAndroid to WebContentsObserver

BUG=396118

Review URL: https://codereview.chromium.org/650333003

Cr-Commit-Position: refs/heads/master@{#300426}

chrome/android/java/src/org/chromium/chrome/browser/WebsiteSettingsPopupLegacy.java

@@ -25,7 +25,7 @@ import android.widget.TextView;
 import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.base.CalledByNative;
 import org.chromium.chrome.R;
-import org.chromium.content.browser.WebContentsObserverAndroid;
+import org.chromium.content.browser.WebContentsObserver;
 import org.chromium.content_public.browser.WebContents;
 
 import java.net.URISyntaxException;
@@ -67,8 +67,8 @@ public class WebsiteSettingsPopupLegacy implements OnClickListener {
         mDialog.setCanceledOnTouchOutside(true);
         // This needs to come after other member initialization.
         mNativeWebsiteSettingsPopupLegacy = nativeInit(this, webContents);
-        final WebContentsObserverAndroid webContentsObserver =
-                new WebContentsObserverAndroid(mWebContents) {
+        final WebContentsObserver webContentsObserver =
+                new WebContentsObserver(mWebContents) {
             @Override
             public void navigationEntryCommitted() {
                 // If a navigation is committed (e.g. from in-page redirect), the data we're

content/public/android/java/src/org/chromium/content/browser/WebContentsObserverAndroid.java

-// Copyright 2012 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.content.browser;
-
-import org.chromium.content_public.browser.WebContents;
-
-/**
- * @deprecated This class has been renamed to {@link WebContentsObserver} and
- * will be removed when all usages have been removed. See http://crbug.com/3961
- */
-@Deprecated
-public abstract class WebContentsObserverAndroid extends WebContentsObserver {
-
-    public WebContentsObserverAndroid(WebContents webContents) {
-        super(webContents);
-    }
-}