OOPIF: Send page-level focus messages to all processes rendering a page.

content/browser/web_contents/web_contents_impl.cc

 // Copyright (c) 2012 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.
 
 #include "content/browser/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
@@ skipping 1567 matching lines @@
 }
 
 RenderWidgetHostInputEventRouter* WebContentsImpl::GetInputEventRouter() {
   // Currently only supported in site per process mode (--site-per-process).
   if (!rwh_input_event_router_.get() && !is_being_destroyed_ &&
       SiteIsolationPolicy::AreCrossProcessFramesPossible())
     rwh_input_event_router_.reset(new RenderWidgetHostInputEventRouter);
   return rwh_input_event_router_.get();
 }
 
+void WebContentsImpl::SendFocusToCrossProcessRenderWidgets(bool is_focused) {
+  // Focus loss may occur while this WebContents is being destroyed.  Don't
+  // send the message in this case, as the main frame's RenderFrameHost, which
+  // is used when getting all RenderWidgetHostViews, has already been cleared.
+  if (is_being_destroyed_)

[alexmos, 2015/10/09 20:23:29]

For reference, the call stack leading to this is at
http://pastebin.com/Z9h2d80n.  Without this check, some tests crashed doing the
view enumeration below in AddRenderWidgetHostViewToSet, when trying to access
the root's RFH (which is null).

[Charlie Reis, 2015/10/09 21:21:51]

Acknowledged.

+    return;
+
+  for (RenderWidgetHostView* view : GetRenderWidgetHostViewsInTree()) {
+    if (!view || view == GetRenderWidgetHostView())

[Charlie Reis, 2015/10/09 21:21:51]

Hmm.  It looks like any widget (including subframe widgets) can call this
method, so why would we compare against the main frame's widget here?  That
would make us skip the main frame, as well as duplicate the message to the
widget that called this method.

[alexmos, 2015/10/16 16:50:45]

This is supposed to be only called from main widgets; RWHI now checks
IsRenderView before calling this, and this check is removed.

+      continue;
+
+    RenderWidgetHostImpl* rwh =
+        RenderWidgetHostImpl::From(view->GetRenderWidgetHost());
+    rwh->Send(new InputMsg_SetFocus(rwh->GetRoutingID(), is_focused));

[Charlie Reis, 2015/10/09 21:21:51]

As in the test, I'm wondering why we want to tell all the other widgets that
some other widget got focus.  It seems like they would want to know that they've
lost focus, if they had it.  (Or at least, which frame has it now.)

[alexmos, 2015/10/16 16:50:45]

I think we've cleared this up in earlier comments, but regardless, I'm now
sending this through main frame's proxies, not widgets.

+  }
+}
+
 void WebContentsImpl::EnterFullscreenMode(const GURL& origin) {
   // This method is being called to enter renderer-initiated fullscreen mode.
   // Make sure any existing fullscreen widget is shut down first.
   RenderWidgetHostView* const widget_view = GetFullscreenRenderWidgetHostView();
   if (widget_view)
     RenderWidgetHostImpl::From(widget_view->GetRenderWidgetHost())->Shutdown();
 
   if (delegate_)
     delegate_->EnterFullscreenModeForTab(this, origin);
 
@@ skipping 3041 matching lines @@
   return NULL;
 }
 
 void WebContentsImpl::SetForceDisableOverscrollContent(bool force_disable) {
   force_disable_overscroll_content_ = force_disable;
   if (view_)
     view_->SetOverscrollControllerEnabled(CanOverscrollContent());
 }
 
 }  // namespace content