Notifying the Out of Process Renderer about Visibility Change of a Remote Frame

content/browser/frame_host/cross_process_frame_connector.cc

 // 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.
 
 #include "content/browser/frame_host/cross_process_frame_connector.h"
 
 #include "cc/surfaces/surface.h"
 #include "cc/surfaces/surface_manager.h"
 #include "content/browser/compositor/surface_utils.h"
 #include "content/browser/frame_host/frame_tree.h"
@@ skipping 25 matching lines @@
 bool CrossProcessFrameConnector::OnMessageReceived(const IPC::Message& msg) {
   bool handled = true;
 
   IPC_BEGIN_MESSAGE_MAP(CrossProcessFrameConnector, msg)
     IPC_MESSAGE_HANDLER(FrameHostMsg_CompositorFrameSwappedACK,
                         OnCompositorFrameSwappedACK)
     IPC_MESSAGE_HANDLER(FrameHostMsg_ReclaimCompositorResources,
                         OnReclaimCompositorResources)
     IPC_MESSAGE_HANDLER(FrameHostMsg_ForwardInputEvent, OnForwardInputEvent)
     IPC_MESSAGE_HANDLER(FrameHostMsg_FrameRectChanged, OnFrameRectChanged)
+    IPC_MESSAGE_HANDLER(FrameHostMsg_VisibilityChanged, OnVisibilityChanged)
     IPC_MESSAGE_HANDLER(FrameHostMsg_InitializeChildFrame,
                         OnInitializeChildFrame)
     IPC_MESSAGE_HANDLER(FrameHostMsg_SatisfySequence, OnSatisfySequence)
     IPC_MESSAGE_HANDLER(FrameHostMsg_RequireSequence, OnRequireSequence)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
 
   return handled;
 }
 
@@ skipping 153 matching lines @@
     return;
   }
 }
 
 void CrossProcessFrameConnector::OnFrameRectChanged(
     const gfx::Rect& frame_rect) {
   if (!frame_rect.size().IsEmpty())
     SetSize(frame_rect);
 }
 
+void CrossProcessFrameConnector::OnVisibilityChanged(bool visible) {
+  if (!view_)
+    return;
+  view_->SetVisibility(visible);

[kenrb, 2015/11/04 21:57:42]

Why not just call Show() or Hide() directly, rather than adding a new method to
RWHVChildFrame?

[EhsanK, 2015/11/05 15:57:39]

This is a provision for <webview>.
My understanding is that those methods will get called when we call WasHidden or
WasShown on the WebContentsImpl. That being said, in case of <webview>, we will
only need to forward the call to those of the WebContentsImpl and then the
RWHVCF ones will be called. If we call Show() and Hide() directly here, and then
forward those calls to WebContentsImpl, the Show() and Hide() will get called
again (twice). That is the only reason I though of having an extra function like
this so that I can add <webview> code later in it.

I can remove but maybe add it again later when fixing the <webview> issue?

[kenrb, 2015/11/11 16:09:33]

This sounds a bit hacky, but I don't know the <webview> code well enough to
suggest anything better.

Can we still remove RWHVCF::SetVisibility() by putting the check here instead?
You should be able to call
view_->GetRenderWidgetHost()->delegate()->DidForwardVisibilityChangeToGuest(visible),
and then call Hide() or Show() directly, correct?

[EhsanK, 2015/11/11 19:13:18]

Done. I will also add Istiaque to take a look at this then.

+}
+
 void CrossProcessFrameConnector::SetDeviceScaleFactor(float scale_factor) {
   device_scale_factor_ = scale_factor;
   // The RenderWidgetHost is null in unit tests.
   if (view_ && view_->GetRenderWidgetHost()) {
     RenderWidgetHostImpl* child_widget =
         RenderWidgetHostImpl::From(view_->GetRenderWidgetHost());
     child_widget->NotifyScreenInfoChanged();
   }
 }
 
@@ skipping 12 matching lines @@
   // in the case of nested WebContents.
   while (top_host->frame_tree_node()->render_manager()->ForInnerDelegate()) {
     top_host = top_host->frame_tree_node()->render_manager()->
         GetOuterDelegateNode()->frame_tree()->root()->current_frame_host();
   }
 
   return static_cast<RenderWidgetHostViewBase*>(top_host->GetView());
 }
 
 }  // namespace content