PlzNavigate: stop navigations when opening a document for write

content/common/frame_messages.h

 // Copyright 2013 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.
 
 // IPC messages for interacting with frames.
 // Multiply-included message file, hence no include guard.
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 869 matching lines @@
 // Tells the renderer that a navigation is ready to commit.  The renderer should
 // request |stream_url| to get access to the stream containing the body of the
 // response.
 IPC_MESSAGE_ROUTED4(FrameMsg_CommitNavigation,
                     content::ResourceResponseHead,    /* response */
                     GURL,                             /* stream_url */
                     content::CommonNavigationParams,  /* common_params */
                     content::RequestNavigationParams  /* request_params */)
 
 // PlzNavigate
+// Informs the renderer that the browser stopped processing a renderer-initiated
+// navigation.
+IPC_MESSAGE_ROUTED0(FrameMsg_DroppedNavigation)

[Nate Chapin, 2017/03/07 18:39:08]

Are there any race conditions that could lead to dropping a subsequent
navigation instead of the intended one? I don't know how much to worry about
that case.

[nasko, 2017/03/09 05:19:28]

Would it help if we add the URL of the navigation the renderer wanted to cancel?
This gives us an extra piece of data to ensure we are cancelling the intended
navigation.

[clamy, 2017/03/13 13:55:57]

We could still have race condition though if we try to request a navigation to
the same url twice. Short of introducing an ID, there's not much to do to
prevent a race from happening.

+
+// PlzNavigate
 // Tells the renderer that a navigation failed with the error code |error_code|
 // and that the renderer should display an appropriate error page.
 IPC_MESSAGE_ROUTED4(FrameMsg_FailedNavigation,
                     content::CommonNavigationParams,  /* common_params */
                     content::RequestNavigationParams, /* request_params */
                     bool,                             /* stale_copy_in_cache */
                     int                               /* error_code */)
 
 // Request to enumerate and return links to all savable resources in the frame
 // Note: this covers only the immediate frame / doesn't cover subframes.
@@ skipping 574 matching lines @@
                     std::string /* http method */,
                     std::string /* mime type */,
                     content::ResourceType /* resource type */)
 
 // PlzNavigate
 // Tells the browser to perform a navigation.
 IPC_MESSAGE_ROUTED2(FrameHostMsg_BeginNavigation,
                     content::CommonNavigationParams,
                     content::BeginNavigationParams)
 
+// PlzNavigate
+// Tells the browser to abort an ongoing renderer-initiated navigation. This is
+// used when the page calls document.open.
+IPC_MESSAGE_ROUTED0(FrameHostMsg_AbortNavigation)
+
 // Sent as a response to FrameMsg_VisualStateRequest.
 // The message is delivered using RenderWidget::QueueMessage.
 IPC_MESSAGE_ROUTED1(FrameHostMsg_VisualStateResponse, uint64_t /* id */)
 
 // Reply to the ExtractSmartClipData message.
 IPC_MESSAGE_ROUTED3(FrameHostMsg_SmartClipDataExtracted,
                     uint32_t /* id */,
                     base::string16 /* text */,
                     base::string16 /* html */)
 
@@ skipping 119 matching lines @@
 // nearest find result in the sending frame.
 IPC_MESSAGE_ROUTED2(FrameHostMsg_GetNearestFindResult_Reply,
                     int /* nfr_request_id */,
                     float /* distance */)
 #endif
 
 // Adding a new message? Stick to the sort order above: first platform
 // independent FrameMsg, then ifdefs for platform specific FrameMsg, then
 // platform independent FrameHostMsg, then ifdefs for platform specific
 // FrameHostMsg.