Force new surface on BrowserPluginGuest reattach.

content/browser/frame_host/render_widget_host_view_guest.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 "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "cc/surfaces/surface.h"
 #include "cc/surfaces/surface_factory.h"
@@ skipping 186 matching lines @@
 base::string16 RenderWidgetHostViewGuest::GetSelectedText() const {
   return platform_view_->GetSelectedText();
 }
 
 void RenderWidgetHostViewGuest::SetTooltipText(
     const base::string16& tooltip_text) {
   if (guest_)
     guest_->SetTooltipText(tooltip_text);
 }
 
+void RenderWidgetHostViewGuest::ClearSurfaceIfNecessary() {

[kenrb, 2015/06/26 14:07:04]

Is there any reason this can't move to RenderWidgetHostViewChildFrame, to reduce
duplication and keep this code more consistent?

[wjmaclean, 2015/06/26 16:25:06]

Done.

+  if (surface_factory_ && !surface_id_.is_null())
+      surface_factory_->Destroy(surface_id_);
+  surface_id_ = cc::SurfaceId();
+}
+
 void RenderWidgetHostViewGuest::OnSwapCompositorFrame(
     uint32 output_surface_id,
     scoped_ptr<cc::CompositorFrame> frame) {
-  if (!guest_)
+  if (!guest_ || !guest_->attached()) {
+    // We shouldn't hang on to a surface while we are detached.
+    ClearSurfaceIfNecessary();
     return;
+  }
 
   last_scroll_offset_ = frame->metadata.root_scroll_offset;
   // When not using surfaces, the frame just gets proxied to
   // the embedder's renderer to be composited.
   if (!frame->delegated_frame_data || !use_surfaces_) {
     guest_->SwapCompositorFrame(output_surface_id,
                                 host_->GetProcess()->GetID(),
                                 host_->GetRoutingID(),
                                 frame.Pass());
     return;
   }
 
   cc::RenderPass* root_pass =
       frame->delegated_frame_data->render_pass_list.back();
 
   gfx::Size frame_size = root_pass->output_rect.size();
   float scale_factor = frame->metadata.device_scale_factor;
 
   guest_->UpdateGuestSizeIfNecessary(frame_size, scale_factor);
 
   // Check whether we need to recreate the cc::Surface, which means the child
   // frame renderer has changed its output surface, or size, or scale factor.
   if (output_surface_id != last_output_surface_id_ && surface_factory_) {
     surface_factory_->Destroy(surface_id_);
     surface_factory_.reset();
   }
   if (output_surface_id != last_output_surface_id_ ||
       frame_size != current_surface_size_ ||
-      scale_factor != current_surface_scale_factor_) {
-    if (surface_factory_ && !surface_id_.is_null())
-      surface_factory_->Destroy(surface_id_);
-    surface_id_ = cc::SurfaceId();
+      scale_factor != current_surface_scale_factor_ ||
+      guest_->has_attached_since_surface_set()) {
+    ClearSurfaceIfNecessary();
     last_output_surface_id_ = output_surface_id;
     current_surface_size_ = frame_size;
     current_surface_scale_factor_ = scale_factor;
   }
 
   if (!surface_factory_) {
     cc::SurfaceManager* manager = GetSurfaceManager();
     surface_factory_ = make_scoped_ptr(new cc::SurfaceFactory(manager, this));
   }
 
@@ skipping 404 matching lines @@
   }
 
   if (blink::WebInputEvent::isGestureEventType(event->type)) {
     host_->ForwardGestureEvent(
         *static_cast<const blink::WebGestureEvent*>(event));
     return;
   }
 }
 
 }  // namespace content