From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Shelley Vohr <shelley.vohr@gmail.com>
Date: Tue, 4 Feb 2020 08:59:32 -0700
Subject: Revert "Remove ContentRendererClient::ShouldFork."

This reverts the CL at https://chromium-review.googlesource.com/c/chromium/src/+/1812128.
We use it to force a new renderer process for navigations, and need to start a new renderer process
for every navigation to keep Node.js working properly. Once Native Modules in the renderer process
are required to be NAPI or context aware (Electron v11), this patch can be removed.

diff --git a/chrome/renderer/chrome_content_renderer_client.cc b/chrome/renderer/chrome_content_renderer_client.cc
index b8379e73d47c82114a155a24292d99651a18224d..fdf94df4a4311cc3222b7ad612691896df7c6f59 100644
--- a/chrome/renderer/chrome_content_renderer_client.cc
+++ b/chrome/renderer/chrome_content_renderer_client.cc
@@ -1278,6 +1278,25 @@ ChromeContentRendererClient::GetProtocolHandlerSecurityLevel() {
 #endif
 }
 
+bool ChromeContentRendererClient::ShouldFork(WebLocalFrame* frame,
+                                             const GURL& url,
+                                             const std::string& http_method,
+                                             bool is_initial_navigation,
+                                             bool is_server_redirect) {
+  DCHECK(!frame->Parent());
+
+  // If |url| matches one of the prerendered URLs, stop this navigation and try
+  // to swap in the prerendered page on the browser process. If the prerendered
+  // page no longer exists by the time the OpenURL IPC is handled, a normal
+  // navigation is attempted.
+  if (prerender_dispatcher_.get() &&
+      prerender_dispatcher_->IsPrerenderURL(url)) {
+    return true;
+  }
+
+  return false;
+}
+
 void ChromeContentRendererClient::WillSendRequest(
     WebLocalFrame* frame,
     ui::PageTransition transition_type,
diff --git a/chrome/renderer/chrome_content_renderer_client.h b/chrome/renderer/chrome_content_renderer_client.h
index 857b350afe980dd79e4c76ebd3cb1be461457f0a..1cac9fc1d8d92d5afe02aa1d1dba05895d4d2672 100644
--- a/chrome/renderer/chrome_content_renderer_client.h
+++ b/chrome/renderer/chrome_content_renderer_client.h
@@ -122,6 +122,11 @@ class ChromeContentRendererClient
       base::SingleThreadTaskRunner* compositor_thread_task_runner) override;
   bool RunIdleHandlerWhenWidgetsHidden() override;
   bool AllowPopup() override;
+  bool ShouldFork(blink::WebLocalFrame* frame,
+                  const GURL& url,
+                  const std::string& http_method,
+                  bool is_initial_navigation,
+                  bool is_server_redirect) override;
   blink::ProtocolHandlerSecurityLevel GetProtocolHandlerSecurityLevel()
       override;
   void WillSendRequest(blink::WebLocalFrame* frame,
diff --git a/content/public/renderer/content_renderer_client.cc b/content/public/renderer/content_renderer_client.cc
index 78174b924c7b8429d1400b51f4a560d750cc0af6..20eee821969cfa32a61cc0c16e216d3821253d77 100644
--- a/content/public/renderer/content_renderer_client.cc
+++ b/content/public/renderer/content_renderer_client.cc
@@ -117,6 +117,14 @@ bool ContentRendererClient::HandleNavigation(
 }
 #endif
 
+bool ContentRendererClient::ShouldFork(blink::WebLocalFrame* frame,
+                                       const GURL& url,
+                                       const std::string& http_method,
+                                       bool is_initial_navigation,
+                                       bool is_server_redirect) {
+  return false;
+}
+
 void ContentRendererClient::WillSendRequest(
     blink::WebLocalFrame* frame,
     ui::PageTransition transition_type,
diff --git a/content/public/renderer/content_renderer_client.h b/content/public/renderer/content_renderer_client.h
index 16d0dd4456f214b14fbdf224ba938ebb1cb63106..4dc340938d54597a315ebb441d769dccb398757d 100644
--- a/content/public/renderer/content_renderer_client.h
+++ b/content/public/renderer/content_renderer_client.h
@@ -210,6 +210,13 @@ class CONTENT_EXPORT ContentRendererClient {
                                 bool is_redirect);
 #endif
 
+  // Returns true if we should fork a new process for the given navigation.
+  virtual bool ShouldFork(blink::WebLocalFrame* frame,
+                          const GURL& url,
+                          const std::string& http_method,
+                          bool is_initial_navigation,
+                          bool is_server_redirect);
+
   // Notifies the embedder that the given frame is requesting the resource at
   // |url|. If the function returns a valid |new_url|, the request must be
   // updated to use it.
diff --git a/content/renderer/render_frame_impl.cc b/content/renderer/render_frame_impl.cc
index efbfb14678cc28dbf3ea918aa6c280e7518a673f..75205d7112eb643392bcdb7368d311adfa14a10a 100644
--- a/content/renderer/render_frame_impl.cc
+++ b/content/renderer/render_frame_impl.cc
@@ -5468,6 +5468,23 @@ void RenderFrameImpl::BeginNavigation(
     // we can do a per-frame check here rather than a process-wide check.
     bool should_fork = HasWebUIScheme(url) || HasWebUIScheme(old_url) ||
                        (enabled_bindings_ & kWebUIBindingsPolicyMask);
+
+    if (!should_fork && url.SchemeIs(url::kFileScheme)) {
+      // Fork non-file to file opens (see https://crbug.com/1031119).  Note that
+      // this may fork unnecessarily if another tab (hosting a file or not)
+      // targeted this one before its initial navigation, but that shouldn't
+      // cause a problem.
+      should_fork = !old_url.SchemeIs(url::kFileScheme);
+    }
+
+    if (!should_fork) {
+      // Give the embedder a chance.
+      bool is_initial_navigation = render_view_->history_list_length_ == 0;
+      should_fork = GetContentClient()->renderer()->ShouldFork(
+          frame_, url, info->url_request.HttpMethod().Utf8(),
+          is_initial_navigation, false /* is_redirect */);
+    }
+
     if (should_fork) {
       OpenURL(std::move(info));
       return;  // Suppress the load here.