New WebContents created via ctrl-click should be in a new process.

chrome/browser/ui/browser_navigator_params.h

 // Copyright 2015 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.
 
 #ifndef CHROME_BROWSER_UI_BROWSER_NAVIGATOR_PARAMS_H_
 #define CHROME_BROWSER_UI_BROWSER_NAVIGATOR_PARAMS_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 114 matching lines @@
   // CURRENT_TAB          "     "     "                     NEW_FOREGROUND_TAB
   // OFF_THE_RECORD       target browser profile is incog.  NEW_FOREGROUND_TAB
   //
   // If disposition is NEW_BACKGROUND_TAB, TabStripModel::ADD_ACTIVE is
   // removed from |tabstrip_add_types| automatically.
   // If disposition is one of NEW_WINDOW, NEW_POPUP, NEW_FOREGROUND_TAB or
   // SINGLETON_TAB, then TabStripModel::ADD_ACTIVE is automatically added to
   // |tabstrip_add_types|.
   WindowOpenDisposition disposition;
 
+  // Controls whether newly created web contents (in case if |disposition| asks

[Charlie Reis, 2017/04/19 20:11:11]

nit: Drop "if"

[Łukasz Anforowicz, 2017/04/20 01:11:29]

Done.

+  // for a new tab or window) should attempt to reuse the renderer process of
+  // |source_site_instance|.  For example - new contents created after
+  // ctrl-clicking a link should use always a new renderer, but
+  // chrome.windows.create extensions API should try to keep the new contents in
+  // the same extension process (if same-site).
+  bool use_new_renderer_for_new_contents;

[Charlie Reis, 2017/04/19 20:11:11]

I'm trying to think of alternatives for the name (e.g.,
new_contents_is_unrelated?), but the name you have seems clear enough.  I'm ok
with it.

+
   // Sets browser->is_trusted_source. Default is false.
   bool trusted_source;
 
   // The transition type of the navigation. Default is
   // ui::PAGE_TRANSITION_LINK when target_contents is specified in the
   // constructor.
   ui::PageTransition transition;
 
   // Whether this navigation was initiated by the renderer process. Default is
   // false.
@@ skipping 102 matching lines @@
   NavigateParams();
 };
 
 // Copies fields from |params| struct to |nav_params| struct.
 void FillNavigateParamsFromOpenURLParams(chrome::NavigateParams* nav_params,
                                          const content::OpenURLParams& params);
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_UI_BROWSER_NAVIGATOR_PARAMS_H_