Revert of Use FrameIsAd to decide whether to isolate a frame in TopDocumentIsolation mode.

content/public/browser/content_browser_client.cc

 // Copyright (c) 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.
 
 #include "content/public/browser/content_browser_client.h"
 
 #include <utility>
 
 #include "base/files/file_path.h"
 #include "base/guid.h"
@@ skipping 74 matching lines @@
 bool ContentBrowserClient::CanCommitURL(RenderProcessHost* process_host,
                                         const GURL& site_url) {
   return true;
 }
 
 bool ContentBrowserClient::ShouldAllowOpenURL(SiteInstance* site_instance,
                                               const GURL& url) {
   return true;
 }
 
-bool ContentBrowserClient::ShouldIsolateFrameForTopDocumentIsolation(
-    NavigationHandle* navigation_handle,
-    SiteInstance* main_frame_site_instance) {
-  // In absence of customizations above //content layer, TDI mode should isolate
-  // all cross-site frames.  Additionally, isolating all cross-site frames makes
-  // it easier to test TopDocumentIsolation in content_browsertests.
-  return true;
+bool ContentBrowserClient::
+    ShouldFrameShareParentSiteInstanceDespiteTopDocumentIsolation(
+        const GURL& url,
+        SiteInstance* parent_site_instance) {
+  return false;
 }
 
 bool ContentBrowserClient::IsSuitableHost(RenderProcessHost* process_host,
                                           const GURL& site_url) {
   return true;
 }
 
 bool ContentBrowserClient::MayReuseHost(RenderProcessHost* process_host) {
   return true;
 }
@@ skipping 367 matching lines @@
   return nullptr;
 }
 
 std::vector<std::unique_ptr<URLLoaderThrottle>>
 ContentBrowserClient::CreateURLLoaderThrottles(
     const base::Callback<WebContents*()>& wc_getter) {
   return std::vector<std::unique_ptr<URLLoaderThrottle>>();
 }
 
 }  // namespace content