PlzNavigate: stop navigations when opening a document for write

content/common/navigation_params.h

 // Copyright 2014 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 CONTENT_COMMON_NAVIGATION_PARAMS_H_
 #define CONTENT_COMMON_NAVIGATION_PARAMS_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 124 matching lines @@
   // TODO(clamy): See if it is possible to reuse this in
   // ResourceMsg_Request_Params.
   BeginNavigationParams();
   BeginNavigationParams(
       std::string headers,
       int load_flags,
       bool has_user_gesture,
       bool skip_service_worker,
       RequestContextType request_context_type,
       blink::WebMixedContentContextType mixed_content_context_type,
-      const base::Optional<url::Origin>& initiator_origin);
+      const base::Optional<url::Origin>& initiator_origin,
+      int renderer_navigation_id);
   BeginNavigationParams(const BeginNavigationParams& other);
   ~BeginNavigationParams();
 
   // Additional HTTP request headers.
   std::string headers;
 
   // net::URLRequest load flags (net::LOAD_NORMAL) by default).
   int load_flags;
 
   // True if the request was user initiated.
@@ skipping 13 matching lines @@
   std::string searchable_form_encoding;
 
   // Indicates the initiator of the request. In auxilliary navigations, this is
   // the origin of the document that triggered the navigation. This parameter
   // can be null during browser-initiated navigations.
   base::Optional<url::Origin> initiator_origin;
 
   // If the transition type is a client side redirect, then this holds the URL
   // of the page that had the client side redirect.
   GURL client_side_redirect_url;
+
+  // ID provided by the renderer to identify this navigation. It will be sent
+  // back to the renderer if the browser decides to drop the navigation.
+  // -1 is this navigation wasn't renderer-initiated.

[nasko, 2017/03/16 21:23:14]

nit: "Value of -1 means this ..."

Why not define a constant in this header, something like kInvalidNavigationId,
so it can be used in the rest of the codebase? It is more meaningful to read the
constant name than -1 and less error prone.

[clamy, 2017/03/17 15:19:11]

Done.

+  int renderer_navigation_id;
 };
 
 // Provided by the browser -----------------------------------------------------
 //
 // These structs are sent by the browser to the renderer to start/commit a
 // navigation depending on whether browser-side navigation is enabled.
 // Parameters used both in the current architecture and PlzNavigate should be
 // put in RequestNavigationParams.  Parameters only used by the current
 // architecture should go in StartNavigationParams.
 
@@ skipping 176 matching lines @@
   ~NavigationParams();
 
   CommonNavigationParams common_params;
   StartNavigationParams start_params;
   RequestNavigationParams request_params;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_NAVIGATION_PARAMS_H_