Allow MimeHandlerViewGuest be embedded inside OOPIFs

content/browser/browser_plugin/browser_plugin_guest.cc

Index: content/browser/browser_plugin/browser_plugin_guest.cc
diff --git a/content/browser/browser_plugin/browser_plugin_guest.cc b/content/browser/browser_plugin/browser_plugin_guest.cc
index bcb8464383290287d0f6998aa759a6589b3020f2..9edbcc40defa4999cb0c46b9d6f6d57b10b8edca 100644
--- a/content/browser/browser_plugin/browser_plugin_guest.cc
+++ b/content/browser/browser_plugin/browser_plugin_guest.cc
@@ -107,6 +107,8 @@ BrowserPluginGuest::BrowserPluginGuest(bool has_render_view,
       ignore_dragged_url_(true),
       delegate_(delegate),
       can_use_cross_process_frames_(delegate->CanUseCrossProcessFrames()),
+      embedder_process_id_(0),

[Charlie Reis, 2016/10/18 22:52:20]

ChildProcessHost::kInvalidUniqueID

[EhsanK, 2016/10/20 21:41:17]

Thanks. Used in mime_handler_view_guest.cc.

+      embedder_routing_id_(MSG_ROUTING_NONE),
       weak_ptr_factory_(this) {
   DCHECK(web_contents);
   DCHECK(delegate);
@@ -135,10 +137,13 @@ int BrowserPluginGuest::GetGuestProxyRoutingID() {
   // owners in different processes. We probably need to clear the
   // |guest_proxy_routing_id_| and perform any necessary cleanup on Detach
   // to enable this.
-  SiteInstance* owner_site_instance = owner_web_contents_->GetSiteInstance();
-  int proxy_routing_id =
-      GetWebContents()->GetFrameTree()->root()->render_manager()->
-          CreateRenderFrameProxy(owner_site_instance);
+  SiteInstance* owner_site_instance =
+      GetEmbedderFrame()->render_view_host()->GetSiteInstance();
+  int proxy_routing_id = GetWebContents()
+                             ->GetFrameTree()
+                             ->root()
+                             ->render_manager()
+                             ->CreateRenderFrameProxy(owner_site_instance);
   guest_proxy_routing_id_ = RenderFrameProxyHost::FromID(
       owner_site_instance->GetProcess()->GetID(), proxy_routing_id)
           ->GetRenderViewHost()->GetRoutingID();
@@ -169,6 +174,37 @@ void BrowserPluginGuest::WillDestroy() {
   attached_ = false;
 }
 
+WebContents* BrowserPluginGuest::RegisterEmbedderID(int process_id,
+                                                    int routing_id) {
+  RenderFrameHostImpl* rfh =
+      RenderFrameHostImpl::FromID(process_id, routing_id);
+
+  // Both |process_id| and |routing_id| are reported from the renderer side. For

[Charlie Reis, 2016/10/18 22:52:20]

Renderer processes should never be told process IDs, and we shouldn't be
trusting them to send up process/routing ID pairs.  (They could send up any
values they want.)  Can we do this without getting the values from the renderer?

(That said, I don't actually see where the values are being sent by the
renderer, so maybe the comment is wrong?)

[EhsanK, 2016/10/20 21:41:17]

I see. I moved the logic to initialize the embedder process/routing ID into
extensions_guest_view_message_filter.cc where we first receive the IPC to create
the MimeHandlerViewGuest
(ExtensionsGuestViewHostMsg_CreateMimeHandlerViewGuest). There we already have
the (process id, routing id) of the embedder frame.

+  // invalid values, |rfh| will be nullptr.
+  if (!rfh)
+    return nullptr;
+
+  // For now consider the |rfh| as the rightful embedder. The GuestViewManager
+  // will later decide if this |rfh| could be an embedder of the BrowserPlugin.
+  embedder_process_id_ = process_id;
+  embedder_routing_id_ = routing_id;
+
+  return static_cast<WebContentsImpl*>(rfh->delegate());
+}
+
+RenderFrameHostImpl* BrowserPluginGuest::GetEmbedderFrame() const {
+  RenderFrameHostImpl* rfh =
+      RenderFrameHostImpl::FromID(embedder_process_id_, embedder_routing_id_);
+
+  // In <webview> we get here before GuestViewManager::AttachGuest is called.
+  // Our best bet for now is to rely on |owner_web_contents_| main frame. This
+  // is incorrect is <webview> is at some point embedded inside an OOPIF.

[Charlie Reis, 2016/10/18 22:52:20]

Typo (too many "is"'s)

[EhsanK, 2016/10/20 21:41:17]

Thanks! This block is removed now however.

+  if (!rfh)
+    rfh = owner_web_contents_ ? owner_web_contents_->GetMainFrame() : nullptr;
+
+  return rfh;
+}
+
 void BrowserPluginGuest::Init() {
   if (initialized_)
     return;
@@ -241,11 +277,11 @@ bool BrowserPluginGuest::OnMessageReceivedFromEmbedder(
   RenderWidgetHostViewGuest* rwhv = static_cast<RenderWidgetHostViewGuest*>(
       web_contents()->GetRenderWidgetHostView());
   // Until the guest is attached, it should not be handling input events.
-  if (attached() && rwhv &&
+  if (attached() && rwhv && GetEmbedderFrame() &&
+      GetEmbedderFrame()->GetRenderWidgetHost() &&
       rwhv->OnMessageReceivedFromEmbedder(
-          message,
-          RenderWidgetHostImpl::From(
-              embedder_web_contents()->GetRenderViewHost()->GetWidget()))) {
+          message, RenderWidgetHostImpl::From(
+                       GetEmbedderFrame()->GetRenderWidgetHost()))) {
     return true;
   }
 
@@ -373,9 +409,10 @@ bool BrowserPluginGuest::IsGuest(RenderViewHostImpl* render_view_host) {
 }
 
 RenderWidgetHostView* BrowserPluginGuest::GetOwnerRenderWidgetHostView() {
-  if (!owner_web_contents_)
-    return nullptr;
-  return owner_web_contents_->GetRenderWidgetHostView();
+  if (GetEmbedderFrame())
+    return GetEmbedderFrame()->GetView();
+
+  return nullptr;
 }
 
 void BrowserPluginGuest::UpdateVisibility() {
@@ -447,8 +484,8 @@ void BrowserPluginGuest::ResendEventToEmbedder(
     return;
 
   DCHECK(browser_plugin_instance_id_);
-  RenderWidgetHostViewBase* view = static_cast<RenderWidgetHostViewBase*>(
-      embedder_web_contents()->GetMainFrame()->GetView());
+  RenderWidgetHostViewBase* view =
+      static_cast<RenderWidgetHostViewBase*>(GetEmbedderFrame()->GetView());
 
   gfx::Vector2d offset_from_embedder = guest_window_rect_.OffsetFromOrigin();
   if (event.type == blink::WebInputEvent::GestureScrollUpdate) {
@@ -504,7 +541,8 @@ void BrowserPluginGuest::SendMessageToEmbedder(IPC::Message* msg) {
     pending_messages_.push_back(linked_ptr<IPC::Message>(msg));
     return;
   }
-  owner_web_contents_->Send(msg);
+
+  GetEmbedderFrame()->GetRenderWidgetHost()->Send(msg);
 }
 
 void BrowserPluginGuest::DragSourceEndedAt(int client_x, int client_y,
@@ -746,6 +784,7 @@ void BrowserPluginGuest::Attach(
     int browser_plugin_instance_id,
     WebContentsImpl* embedder_web_contents,
     const BrowserPluginHostMsg_Attach_Params& params) {
+  DCHECK_EQ(GetEmbedderFrame()->delegate(), embedder_web_contents);
   browser_plugin_instance_id_ = browser_plugin_instance_id;
   // The guest is owned by the embedder. Attach is queued up so we cannot
   // change embedders before attach completes. If the embedder goes away,