PlzNavigate: stop navigations when opening a document for write

content/common/navigation_params.h

Index: content/common/navigation_params.h
diff --git a/content/common/navigation_params.h b/content/common/navigation_params.h
index c23cada787c82d75e9f1d9837b14ceb52fcb81ac..317ca4d37e22c028a9e412498e05c8b292dcad02 100644
--- a/content/common/navigation_params.h
+++ b/content/common/navigation_params.h
@@ -156,7 +156,9 @@ struct CONTENT_EXPORT CommonNavigationParams {
 };
 
 // Provided by the renderer ----------------------------------------------------
-//
+
+const int kInvalidRenderNavigationId = -1;
+
 // This struct holds parameters sent by the renderer to the browser. It is only
 // used in PlzNavigate (since in the current architecture, the renderer does not
 // inform the browser of navigations until they commit).
@@ -175,7 +177,8 @@ struct CONTENT_EXPORT BeginNavigationParams {
       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();
 
@@ -209,6 +212,12 @@ struct CONTENT_EXPORT BeginNavigationParams {
   // 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.
+  // kInvalidRenderNavigationId means that this navigation wasn't initiated by
+  // the renderer process through the BeginNavigation IPC.
+  int renderer_navigation_id;
 };
 
 // Provided by the browser -----------------------------------------------------