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 e9c8c71a0b2e7a431f14b873a114e741a4c129fb..5db4a2f36da1761f94d7ce58483d4d6544b8daf9 100644
--- a/chrome/renderer/chrome_content_renderer_client.cc
+++ b/chrome/renderer/chrome_content_renderer_client.cc
@@ -1275,6 +1275,25 @@ 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 6aea489e574bd0a8bc882d2f2d29e4929f8ce261..2397ccf48fa54e678652b93896665f89a039a992 100644
--- a/content/public/renderer/content_renderer_client.cc
+++ b/content/public/renderer/content_renderer_client.cc
@@ -115,6 +115,14 @@ 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 536b5a72f4994bde01c6c96ffbca74499ad39a7c..0faa12629b99ea9f5079b53c16f8d6b4b39a41d7 100644
--- a/content/renderer/render_frame_impl.cc
+++ b/content/renderer/render_frame_impl.cc
@@ -5502,6 +5502,23 @@ 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.