Browser Plugin: New Implementation (Browser Side)

content/browser/browser_plugin/browser_plugin_host_embedder_delegate.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/browser_plugin/browser_plugin_host_embedder_delegate.h"
+
+#include "base/time.h"
+#include "content/browser/browser_plugin/browser_plugin_host_guest_delegate.h"
+#include "content/browser/browser_plugin/browser_plugin_host_guest_role.h"
+#include "content/browser/renderer_host/render_view_host_impl.h"
+#include "content/browser/renderer_host/render_widget_host_impl.h"
+#include "content/browser/web_contents/web_contents_impl.h"
+#include "content/common/browser_plugin_messages.h"
+#include "content/common/view_messages.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/render_widget_host_view.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "content/public/browser/web_contents_view.h"
+#include "content/public/common/url_constants.h"
+#include "ui/gfx/size.h"
+
+namespace content {
+
+BrowserPluginHostEmbedderDelegate::BrowserPluginHostEmbedderDelegate(
+    WebContentsImpl* web_contents) : WebContentsObserver(web_contents) {
+}
+
+BrowserPluginHostEmbedderDelegate::~BrowserPluginHostEmbedderDelegate() {
+}
+
+BrowserPluginHostGuestDelegate* BrowserPluginHostEmbedderDelegate::
+    GetGuestByInstanceID(int instance_id) const {
+  ContainerInstanceMap::const_iterator it =
+      guests_by_instance_id_.find(instance_id);
+  if (it != guests_by_instance_id_.end())
+    return it->second;
+  return NULL;
+}
+
+void BrowserPluginHostEmbedderDelegate::AddGuest(int instance_id,
+    BrowserPluginHostGuestDelegate* guest,
+    int64 frame_id) {
+  DCHECK(guests_by_instance_id_.find(instance_id) ==
+      guests_by_instance_id_.end());
+  guests_by_instance_id_[instance_id] = guest;
+  guests_[guest->web_contents()] = frame_id;
+}
+
+void BrowserPluginHostEmbedderDelegate::NavigateGuest(
+    RenderViewHost* render_view_host,
+    int instance_id,
+    int64 frame_id,
+    const std::string& src,
+    const gfx::Size& size) {
+  BrowserPluginHostGuestDelegate* guest = GetGuestByInstanceID(instance_id);
+  WebContentsImpl* guest_web_contents = NULL;
+  GURL url(src);
+  if (!guest) {
+    // The SiteInstance of a given guest is based on the fact that it's a guest

[lazyboy, 2012/08/23 01:41:51]

creis 2012/08/13 17:50:14
=========================
nit: Please move this comment above the host declaration on line 102.

Also, it's unfortunate we don't have any way to enforce that this is in a
platform app.  Are there things that will break if someone tries to create a
BrowserPlugin elsewhere (e.g., in a WebUI page)?

Also, do we need things to enforce that these guest processes won't share across
apps if the process limit is reached?  (Is there already a bug on file for
this?)

lazyboy:
========
re: will browser plugin work other than platform app (e.g. WebUI)?
I don't know what the class WebUI represent, I'm assuming it's regular html
page, in that case it works on a regular page.

re: do we need things to enforce that these guest processes won't share across
apps if the process limit is reached?  (Is there already a bug on file for
this?)
Should I file bug for this?

[Charlie Reis, 2012/08/24 00:28:32]

WebUI pages are special privileged pages in Chrome, like the New Tab Page and
Settings page.  There has been some discussion of allowing browser plugins
within such a page, and I'm concerned that won't work.

Please note that there currently should be no way to include a browser plugin
inside a regular page.  The computation of site here is assuming that the
browser plugin will only be instantiated inside an app, so that the "host" will
be the app's ID.
No, http://crbug.com/131810 will cover it.

+    // in addition to which platform application the guest belongs to, rather
+    // than the URL that the guest is being navigated to.
+    std::string host = render_view_host->GetSiteInstance()->GetSite().host();
+    GURL guest_site(
+        base::StringPrintf("%s://%s", chrome::kGuestScheme, host.c_str()));
+    SiteInstance* guest_site_instance =
+        SiteInstance::CreateForURL(web_contents()->GetBrowserContext(),
+                                   guest_site);
+    guest_web_contents =
+        static_cast<WebContentsImpl*>(
+            WebContents::Create(web_contents()->GetBrowserContext(),
+                                guest_site_instance,
+                                MSG_ROUTING_NONE,
+                                NULL, // base WebContents
+                                NULL  // session storage namespace
+                                ));
+
+    BrowserPluginHostGuestRole* guest_role = guest_web_contents->AddGuestRole(
+        instance_id,
+        render_view_host->GetProcess());
+    guest = guest_role->GetDelegate();
+    guest->set_embedder_render_process_host(
+        render_view_host->GetProcess());
+
+    guest_web_contents->GetMutableRendererPrefs()->
+        throttle_input_events = false;
+    AddGuest(instance_id, guest, frame_id);
+  } else {
+    guest_web_contents = static_cast<WebContentsImpl*>(guest->web_contents());
+  }
+  guest->web_contents()->SetDelegate(guest);
+  guest->web_contents()->GetController().LoadURL(url,
+                                                 Referrer(),
+                                                 PAGE_TRANSITION_AUTO_SUBFRAME,
+                                                 std::string());
+  if (!size.IsEmpty())
+    guest_web_contents->GetView()->SizeContents(size);
+}
+
+void BrowserPluginHostEmbedderDelegate::UpdateRectACK(int instance_id,
+                                                      int message_id,
+                                                      const gfx::Size& size) {
+  BrowserPluginHostGuestDelegate* guest = GetGuestByInstanceID(instance_id);
+  if (guest) {
+    guest->UpdateRectACK(message_id, size);
+  }
+}
+
+void BrowserPluginHostEmbedderDelegate::ResizeGuest(int instance_id,
+                                                    TransportDIB* damage_buffer,
+                                                    int width,
+                                                    int height,
+                                                    bool resize_pending,
+                                                    float scale_factor) {
+  BrowserPluginHostGuestDelegate* guest = GetGuestByInstanceID(instance_id);
+  if (!guest)
+    return;
+  WebContentsImpl* guest_web_contents =
+      static_cast<WebContentsImpl*>(guest->web_contents());
+  guest->SetDamageBuffer(damage_buffer, gfx::Size(width, height), scale_factor);
+  if (!resize_pending)
+    guest_web_contents->GetView()->SizeContents(gfx::Size(width, height));
+}
+
+void BrowserPluginHostEmbedderDelegate::SetFocus(int instance_id,
+                                                 bool focused) {
+  BrowserPluginHostGuestDelegate* guest = GetGuestByInstanceID(instance_id);
+  if (guest) {
+    guest->SetFocus(focused);
+  }
+}
+
+void BrowserPluginHostEmbedderDelegate::DestroyGuests() {
+  for (GuestMap::const_iterator it = guests_.begin();
+      it != guests_.end(); ++it) {
+    WebContents* web_contents = it->first;
+    delete web_contents;
+  }
+  guests_.clear();
+  guests_by_instance_id_.clear();
+}
+
+void BrowserPluginHostEmbedderDelegate::HandleInputEvent(
+    int instance_id,
+    RenderViewHost* render_view_host,
+    const gfx::Rect& guest_rect,
+    const WebKit::WebInputEvent& event,
+    IPC::Message* reply_message) {
+  BrowserPluginHostGuestDelegate* guest = GetGuestByInstanceID(instance_id);
+  if (guest) {
+    guest->HandleInputEvent(render_view_host, guest_rect, event, reply_message);
+  }
+}
+
+void BrowserPluginHostEmbedderDelegate::DestroyGuestByInstanceID(
+    int instance_id) {
+  BrowserPluginHostGuestDelegate* guest = GetGuestByInstanceID(instance_id);
+  if (guest) {
+    WebContents* guest_web_contents = guest->web_contents();
+
+    GuestMap::iterator guest_it = guests_.find(guest_web_contents);
+    DCHECK(guest_it != guests_.end());
+
+    guests_.erase(guest_it);
+    guests_by_instance_id_.erase(instance_id);
+
+    guest->Destroy();
+  }
+}
+
+void BrowserPluginHostEmbedderDelegate::DidCommitProvisionalLoadForFrame(
+    int64 frame_id,
+    bool is_main_frame,
+    const GURL& url,
+    PageTransition transition_type,
+    RenderViewHost* render_view_host) {
+  // Clean-up guests that lie in the frame that we're navigating.
+  typedef std::set<WebContents*> GuestSet;
+  GuestSet guests_to_delete;

[lazyboy, 2012/08/23 01:41:51]

creis 2012/08/13 17:50:14
=========================
This looks like it finds all the guests in the frame that navigated.  What about
the subframes of that frame?

e.g., Page A has subframe B, which itself has subframe C.  If B navigates, we
have to destroy any guests present in B or C.

lazyboy:
=========
We won't allow embedding browser tag inside browser tags, not initially at least
(http://crbug.com/141206); I've put a TODO below instead to check this if we
ever
allow nested tags.

[Charlie Reis, 2012/08/24 00:28:32]

Good to know, but that's not quite what I meant.  The embedder page could have
an iframe with a browser tag in it (not a browser tag within a browser tag), and
this code won't clean that up.

+  for (GuestMap::const_iterator it = guests_.begin();
+      it != guests_.end(); ++it) {
+    WebContents* web_contents = it->first;
+    if (it->second == frame_id) {
+      // TODO(lazyboy): If we allow browser tags to be nested, we need to take
+      // care of subframes inside this frame as well.
+      guests_to_delete.insert(web_contents);
+    }
+  }
+  for (GuestSet::const_iterator it = guests_to_delete.begin();
+      it != guests_to_delete.end(); ++it) {
+    int instance_id = static_cast<WebContentsImpl*>(*it)->GetGuestRole()->
+        GetDelegate()->instance_id();
+    DestroyGuestByInstanceID(instance_id);
+  }
+}
+
+void BrowserPluginHostEmbedderDelegate::RenderViewDeleted(
+    RenderViewHost* render_view_host) {
+  DestroyGuests();
+}
+
+void BrowserPluginHostEmbedderDelegate::RenderViewGone(
+    base::TerminationStatus status) {
+  DestroyGuests();
+}
+
+void BrowserPluginHostEmbedderDelegate::WebContentsVisiblitlyChanged(
+    bool visible) {
+  // If the embedder is hidden we need to hide the guests as well.
+  for (GuestMap::const_iterator it = guests_.begin();
+      it != guests_.end(); ++it) {
+    WebContents* web_contents = it->first;
+    if (visible)
+      web_contents->WasShown();
+    else
+      web_contents->WasHidden();
+  }
+}
+
+void BrowserPluginHostEmbedderDelegate::PluginDestroyed(
+    int instance_id) {
+  DestroyGuestByInstanceID(instance_id);
+}
+
+}  // namespace content