Move WebUI ownership from the RenderFrameHostManager to the RenderFrameHost.

content/browser/frame_host/render_frame_host_manager.cc

 // Copyright 2013 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/render_frame_host_manager.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/command_line.h"
@@ skipping 12 matching lines @@
 #include "content/browser/frame_host/navigation_request.h"
 #include "content/browser/frame_host/navigator.h"
 #include "content/browser/frame_host/render_frame_host_factory.h"
 #include "content/browser/frame_host/render_frame_host_impl.h"
 #include "content/browser/frame_host/render_frame_proxy_host.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/renderer_host/render_view_host_factory.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/site_instance_impl.h"
 #include "content/browser/webui/web_ui_controller_factory_registry.h"
-#include "content/browser/webui/web_ui_impl.h"
 #include "content/common/frame_messages.h"
 #include "content/common/site_isolation_policy.h"
 #include "content/common/view_messages.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/render_process_host_observer.h"
 #include "content/public/browser/render_widget_host_iterator.h"
 #include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/user_metrics.h"
-#include "content/public/browser/web_ui_controller.h"
 #include "content/public/common/browser_plugin_guest_mode.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/referrer.h"
 #include "content/public/common/url_constants.h"
 
 namespace content {
 
 namespace {
 
 // Helper function to add the FrameTree of the given node's opener to the list
@@ skipping 160 matching lines @@
     RenderViewHostDelegate* render_view_delegate,
     RenderWidgetHostDelegate* render_widget_delegate,
     Delegate* delegate)
     : frame_tree_node_(frame_tree_node),
       delegate_(delegate),
       render_frame_delegate_(render_frame_delegate),
       render_view_delegate_(render_view_delegate),
       render_widget_delegate_(render_widget_delegate),
       proxy_hosts_(new RenderFrameProxyHostMap(this)),
       interstitial_page_(nullptr),
-      should_reuse_web_ui_(false),
+      current_web_ui_is_navigating_(false),
       weak_factory_(this) {
   DCHECK(frame_tree_node_);
 }
 
 RenderFrameHostManager::~RenderFrameHostManager() {
   if (pending_render_frame_host_) {
     scoped_ptr<RenderFrameHostImpl> relic = UnsetPendingRenderFrameHost();
     ShutdownProxiesIfLastActiveFrameInSiteInstance(relic.get());
   }
 
   if (speculative_render_frame_host_) {
     scoped_ptr<RenderFrameHostImpl> relic = UnsetSpeculativeRenderFrameHost();
     ShutdownProxiesIfLastActiveFrameInSiteInstance(relic.get());
   }
 
   ShutdownProxiesIfLastActiveFrameInSiteInstance(render_frame_host_.get());
 
   // Delete any RenderFrameProxyHosts and swapped out RenderFrameHosts.
   // It is important to delete those prior to deleting the current
   // RenderFrameHost, since the CrossProcessFrameConnector (owned by
   // RenderFrameProxyHost) points to the RenderWidgetHostView associated with
   // the current RenderFrameHost and uses it during its destructor.
   ResetProxyHosts();
 
-  // Release the WebUI prior to resetting the current RenderFrameHost, as the
-  // WebUI accesses the RenderFrameHost during cleanup.
-  web_ui_.reset();
-
   // We should always have a current RenderFrameHost except in some tests.
   SetRenderFrameHost(scoped_ptr<RenderFrameHostImpl>());
 }
 
 void RenderFrameHostManager::Init(SiteInstance* site_instance,
                                   int32 view_routing_id,
                                   int32 frame_routing_id,
                                   int32 widget_routing_id) {
   DCHECK(site_instance);
   // TODO(avi): While RenderViewHostImpl is-a RenderWidgetHostImpl, this must
@@ skipping 20 matching lines @@
     return nullptr;
   return render_frame_host_->render_view_host();
 }
 
 RenderViewHostImpl* RenderFrameHostManager::pending_render_view_host() const {
   if (!pending_render_frame_host_)
     return nullptr;
   return pending_render_frame_host_->render_view_host();
 }
 
+WebUIImpl* RenderFrameHostManager::GetNavigatingWebUI() const {
+  if (current_web_ui_is_navigating_)
+    return render_frame_host_->web_ui();
+
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableBrowserSideNavigation)) {
+    if (speculative_render_frame_host_)
+      return speculative_render_frame_host_->web_ui();
+  } else {
+    if (pending_render_frame_host_)
+      return pending_render_frame_host_->web_ui();
+  }
+  return nullptr;
+}
+
 RenderWidgetHostView* RenderFrameHostManager::GetRenderWidgetHostView() const {
   if (interstitial_page_)
     return interstitial_page_->GetView();
   if (render_frame_host_)
     return render_frame_host_->GetView();
   return nullptr;
 }
 
 bool RenderFrameHostManager::ForInnerDelegate() {
   return delegate_->GetOuterDelegateFrameTreeNodeID() !=
@@ skipping 48 matching lines @@
 
 void RenderFrameHostManager::RemoveOuterDelegateFrame() {
   FrameTreeNode* outer_delegate_frame_tree_node =
       FrameTreeNode::GloballyFindByID(
           delegate_->GetOuterDelegateFrameTreeNodeID());
   DCHECK(outer_delegate_frame_tree_node->parent());
   outer_delegate_frame_tree_node->frame_tree()->RemoveFrame(
       outer_delegate_frame_tree_node);
 }
 
-void RenderFrameHostManager::SetPendingWebUI(const GURL& url, int bindings) {
-  pending_web_ui_ = CreateWebUI(url, bindings);
-  pending_and_current_web_ui_.reset();
-}
-
-scoped_ptr<WebUIImpl> RenderFrameHostManager::CreateWebUI(const GURL& url,
-                                                          int bindings) {
-  scoped_ptr<WebUIImpl> new_web_ui(delegate_->CreateWebUIForRenderManager(url));
-
-  // If we have assigned (zero or more) bindings to this NavigationEntry in the
-  // past, make sure we're not granting it different bindings than it had
-  // before.  If so, note it and don't give it any bindings, to avoid a
-  // potential privilege escalation.
-  if (new_web_ui && bindings != NavigationEntryImpl::kInvalidBindings &&
-      new_web_ui->GetBindings() != bindings) {
-    RecordAction(base::UserMetricsAction("ProcessSwapBindingsMismatch_RVHM"));
-    return nullptr;
-  }
-  return new_web_ui.Pass();
-}
-
 RenderFrameHostImpl* RenderFrameHostManager::Navigate(
     const GURL& dest_url,
     const FrameNavigationEntry& frame_entry,
     const NavigationEntryImpl& entry) {
   TRACE_EVENT1("navigation", "RenderFrameHostManager:Navigate",
                "FrameTreeNode id", frame_tree_node_->frame_tree_node_id());
   // Create a pending RenderFrameHost to use for the navigation.
   RenderFrameHostImpl* dest_render_frame_host = UpdateStateForNavigate(
       dest_url,
       // TODO(creis): Move source_site_instance to FNE.
@@ skipping 28 matching lines @@
     // site that is handled via Mojo, then Mojo WebUI code in //chrome will
     // add a service to this RFH's ServiceRegistry).
     dest_render_frame_host->SetUpMojoIfNeeded();
 
     // Recreate the opener chain.
     CreateOpenerProxies(dest_render_frame_host->GetSiteInstance(),
                         frame_tree_node_);
     if (!InitRenderView(dest_render_frame_host->render_view_host(), nullptr))
       return nullptr;
 
+    if (GetNavigatingWebUI()) {
+      GetNavigatingWebUI()->RenderViewCreated(
+          dest_render_frame_host->render_view_host());
+    }
+
     // Now that we've created a new renderer, be sure to hide it if it isn't
     // our primary one.  Otherwise, we might crash if we try to call Show()
     // on it later.
     if (dest_render_frame_host != render_frame_host_) {
       if (dest_render_frame_host->GetView())
         dest_render_frame_host->GetView()->Hide();
     } else {
       // After a renderer crash we'd have marked the host as invisible, so we
       // need to set the visibility of the new View to the correct value here
       // after reload.
@@ skipping 230 matching lines @@
 
   // Make sure any dynamic changes to this frame's sandbox flags that were made
   // prior to navigation take effect.
   CommitPendingSandboxFlags();
 }
 
 void RenderFrameHostManager::CommitPendingIfNecessary(
     RenderFrameHostImpl* render_frame_host,
     bool was_caused_by_user_gesture) {
   if (!pending_render_frame_host_ && !speculative_render_frame_host_) {
-    DCHECK(!should_reuse_web_ui_ || web_ui_);
+    DCHECK(!current_web_ui_is_navigating_ || render_frame_host_->web_ui());
 
     // We should only hear this from our current renderer.
     DCHECK_EQ(render_frame_host_, render_frame_host);
 
-    // Even when there is no pending RVH, there may be a pending Web UI.
-    if (pending_web_ui() || speculative_web_ui_)
+    // A commit is required if there is a navigating WebUI, even without a
+    // pending or speculative RenderFrameHost.
+    if (GetNavigatingWebUI())
       CommitPending();
     return;
   }
 
   if (render_frame_host == pending_render_frame_host_ ||
       render_frame_host == speculative_render_frame_host_) {
     // The pending cross-process navigation completed, so show the renderer.
     CommitPending();
   } else if (render_frame_host == render_frame_host_) {
     if (base::CommandLine::ForCurrentProcess()->HasSwitch(
@@ skipping 322 matching lines @@
   // Subframe navigations will use the current renderer, unless
   // --site-per-process is enabled.
   // TODO(carlosk): Have renderer-initated main frame navigations swap processes
   // if needed when it no longer breaks OAuth popups (see
   // https://crbug.com/440266).
   bool is_main_frame = frame_tree_node_->IsMainFrame();
   if (current_site_instance == dest_site_instance.get() ||
       (!request.browser_initiated() && is_main_frame) ||
       (!is_main_frame && !dest_site_instance->RequiresDedicatedProcess() &&
        !current_site_instance->RequiresDedicatedProcess())) {
-    // Reuse the current RFH if its SiteInstance matches the the navigation's
-    // or if this is a subframe navigation. We only swap RFHs for subframes when
-    // --site-per-process is enabled.
+    // Reuse the current RenderFrameHost if its SiteInstance matches the the
+    // navigation's or if this is a subframe navigation. We only swap RFHs for
+    // subframes when --site-per-process is enabled.
     CleanUpNavigation();
     navigation_rfh = render_frame_host_.get();
 
-    // As SiteInstances are the same, check if the WebUI should be reused.
-    const NavigationEntry* current_navigation_entry =
-        delegate_->GetLastCommittedNavigationEntryForRenderManager();
-    should_reuse_web_ui_ = ShouldReuseWebUI(current_navigation_entry,
-                                            request.common_params().url);
-    if (!should_reuse_web_ui_) {
-      speculative_web_ui_ = CreateWebUI(request.common_params().url,
-                                        request.bindings());
-      // Make sure the current RenderViewHost has the right bindings.
-      if (speculative_web_ui() &&
-          !render_frame_host_->GetProcess()->IsForGuestsOnly()) {
-        render_frame_host_->render_view_host()->AllowBindings(
-            speculative_web_ui()->GetBindings());
-      }
-    }
+    UpdateWebUIOnCurrentFrameHost(
+        request.common_params().url,
+        request.restore_type() != NavigationEntryImpl::RESTORE_NONE,
+        request.bindings());
+
+    DCHECK(!speculative_render_frame_host_);
   } else {
-    // If the SiteInstance for the final URL doesn't match the one from the
-    // speculatively created RenderFrameHost, create a new RenderFrameHost using
-    // this new SiteInstance.
+    // If the current RenderFrameHost cannot be used a new speculative one is
+    // created with the SiteInstance for the current URL.
+
+    // Check if an existing speculative RenderFrameHost can be reused.
     if (!speculative_render_frame_host_ ||
         speculative_render_frame_host_->GetSiteInstance() !=
             dest_site_instance.get()) {
+      // If a previous speculative RenderFrameHost didn't exist or if its
+      // SiteInstace differs from the one for the current URL, a new one needs
+      // to be created.
       CleanUpNavigation();
-      bool success = CreateSpeculativeRenderFrameHost(
-          request.common_params().url, current_site_instance,
-          dest_site_instance.get(), request.bindings());
+      bool success = CreateSpeculativeRenderFrameHost(current_site_instance,
+                                                      dest_site_instance.get());
       DCHECK(success);
     }
+
+    bool changed_web_ui = speculative_render_frame_host_->UpdateWebUI(
+        request.common_params().url, request.bindings());
+    if (changed_web_ui && speculative_render_frame_host_->web_ui()) {
+      speculative_render_frame_host_->web_ui()->RenderViewCreated(
+          speculative_render_frame_host_->render_view_host());
+    }
     DCHECK(speculative_render_frame_host_);
+    DCHECK_EQ(GetNavigatingWebUI(), speculative_render_frame_host_->web_ui());
+
     navigation_rfh = speculative_render_frame_host_.get();
 
     // Check if our current RFH is live.
     if (!render_frame_host_->IsRenderFrameLive()) {
       // The current RFH is not live.  There's no reason to sit around with a
       // sad tab or a newly created RFH while we wait for the navigation to
       // complete. Just switch to the speculative RFH now and go back to normal.
       // (Note that we don't care about on{before}unload handlers if the current
       // RFH isn't live.)
       CommitPending();
     }
+    DCHECK(!current_web_ui_is_navigating_);
   }
   DCHECK(navigation_rfh &&
          (navigation_rfh == render_frame_host_.get() ||
           navigation_rfh == speculative_render_frame_host_.get()));
 
   // If the RenderFrame that needs to navigate is not live (its process was just
   // created or has crashed), initialize it.
   if (!navigation_rfh->IsRenderFrameLive()) {
     // Recreate the opener chain.
     CreateOpenerProxies(navigation_rfh->GetSiteInstance(), frame_tree_node_);
-    if (!InitRenderView(navigation_rfh->render_view_host(), nullptr)) {
+    if (!InitRenderView(navigation_rfh->render_view_host(), nullptr))
       return nullptr;
+
+    if (GetNavigatingWebUI()) {
+      GetNavigatingWebUI()->RenderViewCreated(
+          navigation_rfh->render_view_host());
     }
 
     if (navigation_rfh == render_frame_host_) {
       // TODO(nasko): This is a very ugly hack. The Chrome extensions process
       // manager still uses NotificationService and expects to see a
       // RenderViewHost changed notification after WebContents and
       // RenderFrameHostManager are completely initialized. This should be
       // removed once the process manager moves away from NotificationService.
       // See https://crbug.com/462682.
       delegate_->NotifyMainFrameSwappedFromRenderManager(
           nullptr, render_frame_host_->render_view_host());
     }
   }
 
   return navigation_rfh;
 }
 
 // PlzNavigate
 void RenderFrameHostManager::CleanUpNavigation() {
   CHECK(base::CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kEnableBrowserSideNavigation));
-  speculative_web_ui_.reset();
-  should_reuse_web_ui_ = false;
+  // TODO(carlosk): the discarding of the current RFH WebUI and the cleanup of
+  // the speculative RFH should not always happen together.
+  current_web_ui_is_navigating_ = false;
   if (speculative_render_frame_host_)
     DiscardUnusedFrame(UnsetSpeculativeRenderFrameHost());
 }
 
 // PlzNavigate
 scoped_ptr<RenderFrameHostImpl>
 RenderFrameHostManager::UnsetSpeculativeRenderFrameHost() {
   CHECK(base::CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kEnableBrowserSideNavigation));
   speculative_render_frame_host_->GetProcess()->RemovePendingView();
@@ skipping 172 matching lines @@
   // We can't switch a RenderView between view source and non-view source mode
   // without screwing up the session history sometimes (when navigating between
   // "view-source:http://foo.com/" and "http://foo.com/", Blink doesn't treat
   // it as a new navigation). So require a BrowsingInstance switch.
   if (current_is_view_source_mode != new_is_view_source_mode)
     return true;
 
   return false;
 }
 
-bool RenderFrameHostManager::ShouldReuseWebUI(
-    const NavigationEntry* current_entry,
-    const GURL& new_url) const {
-  NavigationControllerImpl& controller =
-      delegate_->GetControllerForRenderManager();
-  return current_entry && web_ui_ &&
-      (WebUIControllerFactoryRegistry::GetInstance()->GetWebUIType(
-          controller.GetBrowserContext(), current_entry->GetURL()) ==
-       WebUIControllerFactoryRegistry::GetInstance()->GetWebUIType(
-          controller.GetBrowserContext(), new_url));
-}
-
 SiteInstance* RenderFrameHostManager::GetSiteInstanceForNavigation(
     const GURL& dest_url,
     SiteInstance* source_instance,
     SiteInstance* dest_instance,
     SiteInstance* candidate_instance,
     ui::PageTransition transition,
     bool dest_is_restore,
     bool dest_is_view_source_mode) {
   SiteInstance* current_instance = render_frame_host_->GetSiteInstance();
 
@@ skipping 312 matching lines @@
   // The process for the new SiteInstance may (if we're sharing a process with
   // another host that already initialized it) or may not (we have our own
   // process or the existing process crashed) have been initialized. Calling
   // Init multiple times will be ignored, so this is safe.
   if (!new_instance->GetProcess()->Init())
     return;
 
   CreateProxiesForNewRenderFrameHost(old_instance, new_instance);
 
   // Create a non-swapped-out RFH with the given opener.
-  pending_render_frame_host_ = CreateRenderFrame(
-      new_instance, pending_web_ui(), create_render_frame_flags, nullptr);
+  pending_render_frame_host_ =
+      CreateRenderFrame(new_instance, create_render_frame_flags, nullptr);
 }
 
 void RenderFrameHostManager::CreateProxiesForNewRenderFrameHost(
     SiteInstance* old_instance,
     SiteInstance* new_instance) {
   // Only create opener proxies if they are in the same BrowsingInstance.
   if (new_instance->IsRelatedSiteInstance(old_instance)) {
     CreateOpenerProxies(new_instance, frame_tree_node_);
   } else if (SiteIsolationPolicy::AreCrossProcessFramesPossible()) {
     // Ensure that the frame tree has RenderFrameProxyHosts for the
@@ skipping 75 matching lines @@
   }
 
   return RenderFrameHostFactory::Create(
       site_instance, render_view_host, render_frame_delegate_,
       render_widget_delegate_, frame_tree, frame_tree_node_, frame_routing_id,
       widget_routing_id, flags);
 }
 
 // PlzNavigate
 bool RenderFrameHostManager::CreateSpeculativeRenderFrameHost(
-    const GURL& url,
     SiteInstance* old_instance,
-    SiteInstance* new_instance,
-    int bindings) {
+    SiteInstance* new_instance) {
   CHECK(new_instance);
   CHECK_NE(old_instance, new_instance);
-  CHECK(!should_reuse_web_ui_);
-
-  // Note: |speculative_web_ui_| must be initialized before starting the
-  // |speculative_render_frame_host_| creation steps otherwise the WebUI
-  // won't be properly initialized.
-  speculative_web_ui_ = CreateWebUI(url, bindings);
+  CHECK(!current_web_ui_is_navigating_);
 
   // The process for the new SiteInstance may (if we're sharing a process with
   // another host that already initialized it) or may not (we have our own
   // process or the existing process crashed) have been initialized. Calling
   // Init multiple times will be ignored, so this is safe.
   if (!new_instance->GetProcess()->Init())
     return false;
 
   CreateProxiesForNewRenderFrameHost(old_instance, new_instance);
 
   int create_render_frame_flags = 0;
   if (delegate_->IsHidden())
     create_render_frame_flags |= CREATE_RF_HIDDEN;
   speculative_render_frame_host_ =
-      CreateRenderFrame(new_instance, speculative_web_ui_.get(),
-                        create_render_frame_flags, nullptr);
+      CreateRenderFrame(new_instance, create_render_frame_flags, nullptr);
 
-  if (!speculative_render_frame_host_) {
-    speculative_web_ui_.reset();
-    return false;
-  }
-  return true;
+  return !!speculative_render_frame_host_;
 }
 
 scoped_ptr<RenderFrameHostImpl> RenderFrameHostManager::CreateRenderFrame(
     SiteInstance* instance,
-    WebUIImpl* web_ui,
     int flags,
     int* view_routing_id_ptr) {
   bool swapped_out = !!(flags & CREATE_RF_SWAPPED_OUT);
   bool swapped_out_forbidden =
       SiteIsolationPolicy::IsSwappedOutStateForbidden();
 
   CHECK(instance);
   CHECK(!swapped_out_forbidden || !swapped_out);
   CHECK(SiteIsolationPolicy::AreCrossProcessFramesPossible() ||
         frame_tree_node_->IsMainFrame());
@@ skipping 97 matching lines @@
         success = InitRenderFrame(new_render_frame_host.get());
       }
     }
 
     if (success) {
       if (view_routing_id_ptr)
         *view_routing_id_ptr = render_view_host->GetRoutingID();
     }
   }
 
-  // When a new RenderView is created by the renderer process, the new
-  // WebContents gets a RenderViewHost in the SiteInstance of its opener
-  // WebContents. If not used in the first navigation, this RVH is swapped out
-  // and is not granted bindings, so we may need to grant them when swapping it
-  // in.
-  if (web_ui && !new_render_frame_host->GetProcess()->IsForGuestsOnly()) {
-    int required_bindings = web_ui->GetBindings();
-    RenderViewHost* render_view_host =
-        new_render_frame_host->render_view_host();
-    if ((render_view_host->GetEnabledBindings() & required_bindings) !=
-            required_bindings) {
-      render_view_host->AllowBindings(required_bindings);
-    }
-  }
-
   // Returns the new RFH if it isn't swapped out.
   if (success && !swapped_out) {
     DCHECK(new_render_frame_host->GetSiteInstance() == instance);
     return new_render_frame_host.Pass();
   }
   return nullptr;
 }
 
 int RenderFrameHostManager::CreateRenderFrameProxy(SiteInstance* instance) {
   // A RenderFrameProxyHost should never be created in the same SiteInstance as
@@ skipping 98 matching lines @@
     RenderFrameProxyHost* proxy) {
   // Ensure the renderer process is initialized before creating the
   // RenderView.
   if (!render_view_host->GetProcess()->Init())
     return false;
 
   // We may have initialized this RenderViewHost for another RenderFrameHost.
   if (render_view_host->IsRenderViewLive())
     return true;
 
-  // If |render_view_host| is not for a proxy and the navigation is to a WebUI,
-  // and if the RenderView is not in a guest process, tell |render_view_host|
-  // about any bindings it will need enabled.
-  // TODO(carlosk): Move WebUI to RenderFrameHost in https://crbug.com/508850.
-  WebUIImpl* dest_web_ui = nullptr;
-  if (!proxy) {
-    if (base::CommandLine::ForCurrentProcess()->HasSwitch(
-            switches::kEnableBrowserSideNavigation)) {
-      dest_web_ui =
-          should_reuse_web_ui_ ? web_ui_.get() : speculative_web_ui_.get();
-    } else {
-      dest_web_ui = pending_web_ui();
-    }
-  }
-  if (dest_web_ui && !render_view_host->GetProcess()->IsForGuestsOnly()) {
-    render_view_host->AllowBindings(dest_web_ui->GetBindings());
-  } else {
-    // Ensure that we don't create an unprivileged RenderView in a WebUI-enabled
-    // process unless it's swapped out.
-    if (render_view_host->is_active()) {
-      CHECK(!ChildProcessSecurityPolicyImpl::GetInstance()->HasWebUIBindings(
-                render_view_host->GetProcess()->GetID()));
-    }
-  }
-
   int opener_frame_routing_id =
       GetOpenerRoutingID(render_view_host->GetSiteInstance());
 
   bool created = delegate_->CreateRenderViewForRenderManager(
       render_view_host, opener_frame_routing_id,
       proxy ? proxy->GetRoutingID() : MSG_ROUTING_NONE,
       frame_tree_node_->current_replication_state());
 
   if (created && proxy)
     proxy->set_render_frame_proxy_created(true);
@@ skipping 71 matching lines @@
   RenderFrameProxyHost* proxy = GetRenderFrameProxyHost(site_instance);
   if (proxy)
     return proxy->GetRoutingID();
 
   return MSG_ROUTING_NONE;
 }
 
 void RenderFrameHostManager::CommitPending() {
   TRACE_EVENT1("navigation", "RenderFrameHostManager::CommitPending",
                "FrameTreeNode id", frame_tree_node_->frame_tree_node_id());
-  bool browser_side_navigation =
-      base::CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kEnableBrowserSideNavigation);
-
   // First check whether we're going to want to focus the location bar after
   // this commit.  We do this now because the navigation hasn't formally
-  // committed yet, so if we've already cleared |pending_web_ui_| the call chain
+  // committed yet, so if we've already cleared the pending WebUI the call chain
   // this triggers won't be able to figure out what's going on.
   bool will_focus_location_bar = delegate_->FocusLocationBarByDefault();
 
-  // Next commit the Web UI, if any. Either replace |web_ui_| with
-  // |pending_web_ui_|, or clear |web_ui_| if there is no pending WebUI, or
-  // leave |web_ui_| as is if reusing it.
-  DCHECK(!(pending_web_ui_ && pending_and_current_web_ui_));
-  if (pending_web_ui_ || speculative_web_ui_) {
-    DCHECK(!should_reuse_web_ui_);
-    web_ui_.reset(browser_side_navigation ? speculative_web_ui_.release()
-                                          : pending_web_ui_.release());
-  } else if (pending_and_current_web_ui_ || should_reuse_web_ui_) {
-    if (browser_side_navigation) {
-      DCHECK(web_ui_);
-      should_reuse_web_ui_ = false;
-    } else {
-      DCHECK_EQ(pending_and_current_web_ui_.get(), web_ui_.get());
-      pending_and_current_web_ui_.reset();
-    }
-  } else {
-    web_ui_.reset();
-  }
-  DCHECK(!speculative_web_ui_);
-  DCHECK(!should_reuse_web_ui_);
-
-  // It's possible for the pending_render_frame_host_ to be nullptr when we
-  // aren't crossing process boundaries. If so, we just needed to handle the Web
-  // UI committing above and we're done.
   if (!pending_render_frame_host_ && !speculative_render_frame_host_) {
+    DCHECK_EQ(current_web_ui_is_navigating_, !!render_frame_host_->web_ui());
+    current_web_ui_is_navigating_ = false;
+    // If there's no pending/speculative RenderFrameHost then the current
+    // RenderFrameHost is committing.
     if (will_focus_location_bar)
       delegate_->SetFocusToLocationBar(false);
     return;
   }
 
   // Remember if the page was focused so we can focus the new renderer in
   // that case.
   bool focus_render_view = !will_focus_location_bar &&
                            render_frame_host_->GetView() &&
                            render_frame_host_->GetView()->HasFocus();
 
   bool is_main_frame = frame_tree_node_->IsMainFrame();
 
   // Swap in the pending or speculative frame and make it active. Also ensure
   // the FrameTree stays in sync.
   scoped_ptr<RenderFrameHostImpl> old_render_frame_host;
-  if (!browser_side_navigation) {
+  if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableBrowserSideNavigation)) {
     DCHECK(!speculative_render_frame_host_);
     old_render_frame_host =
         SetRenderFrameHost(pending_render_frame_host_.Pass());
   } else {
     // PlzNavigate
     DCHECK(speculative_render_frame_host_);
     old_render_frame_host =
         SetRenderFrameHost(speculative_render_frame_host_.Pass());
   }
 
@@ skipping 149 matching lines @@
   // If we are currently navigating cross-process, we want to get back to normal
   // and then navigate as usual.
   if (pending_render_frame_host_)
     CancelPending();
 
   SiteInstance* current_instance = render_frame_host_->GetSiteInstance();
   scoped_refptr<SiteInstance> new_instance = GetSiteInstanceForNavigation(
       dest_url, source_instance, dest_instance, nullptr, transition,
       dest_is_restore, dest_is_view_source_mode);
 
-  const NavigationEntry* current_entry =
-      delegate_->GetLastCommittedNavigationEntryForRenderManager();
-
   DCHECK(!pending_render_frame_host_);
 
   if (new_instance.get() != current_instance) {
     TRACE_EVENT_INSTANT2(
         "navigation",
         "RenderFrameHostManager::UpdateStateForNavigate:New SiteInstance",
         TRACE_EVENT_SCOPE_THREAD,
         "current_instance id", current_instance->GetId(),
         "new_instance id", new_instance->GetId());
 
     // New SiteInstance: create a pending RFH to navigate.
 
-    // This will possibly create (set to nullptr) a Web UI object for the
-    // pending page. We'll use this later to give the page special access. This
-    // must happen before the new renderer is created below so it will get
-    // bindings. It must also happen after the above conditional call to
-    // CancelPending(), otherwise CancelPending may clear the pending_web_ui_
-    // and the page will not have its bindings set appropriately.
-    SetPendingWebUI(dest_url, bindings);
+    current_web_ui_is_navigating_ = false;
     CreatePendingRenderFrameHost(current_instance, new_instance.get());
+    DCHECK(pending_render_frame_host_);
     if (!pending_render_frame_host_)
       return nullptr;
 
+    pending_render_frame_host_->UpdateWebUI(dest_url, bindings);
+    if (pending_render_frame_host_->web_ui()) {
+      pending_render_frame_host_->web_ui()->RenderViewCreated(
+          pending_render_frame_host_->render_view_host());
+    }
+
+    // We now have a pending RFH and possibly an associated pending WebUI.
+    DCHECK_EQ(GetNavigatingWebUI(), pending_render_frame_host_->web_ui());
+
     // Check if our current RFH is live before we set up a transition.
     if (!render_frame_host_->IsRenderFrameLive()) {
       // The current RFH is not live.  There's no reason to sit around with a
       // sad tab or a newly created RFH while we wait for the pending RFH to
       // navigate.  Just switch to the pending RFH now and go back to normal.
       // (Note that we don't care about on{before}unload handlers if the current
       // RFH isn't live.)
       CommitPending();
       return render_frame_host_.get();
     }
     // Otherwise, it's safe to treat this as a pending cross-process transition.
 
-    // We now have a pending RFH.
-    DCHECK(pending_render_frame_host_);
-
     // We need to wait until the beforeunload handler has run, unless we are
     // transferring an existing request (in which case it has already run).
     // Suspend the new render view (i.e., don't let it send the cross-process
     // Navigate message) until we hear back from the old renderer's
     // beforeunload handler.  If the handler returns false, we'll have to
     // cancel the request.
-    //
     DCHECK(!pending_render_frame_host_->are_navigations_suspended());
     bool is_transfer = transferred_request_id != GlobalRequestID();
     if (is_transfer) {
       // We don't need to stop the old renderer or run beforeunload/unload
       // handlers, because those have already been done.
       DCHECK(cross_site_transferring_request_->request_id() ==
              transferred_request_id);
     } else {
       // Also make sure the old render view stops, in case a load is in
       // progress.  (We don't want to do this for transfers, since it will
@@ skipping 14 matching lines @@
 
   // Otherwise the same SiteInstance can be used.  Navigate render_frame_host_.
 
   // It's possible to swap out the current RFH and then decide to navigate in it
   // anyway (e.g., a cross-process navigation that redirects back to the
   // original site).  In that case, we have a proxy for the current RFH but
   // haven't deleted it yet.  The new navigation will swap it back in, so we can
   // delete the proxy.
   proxy_hosts_->Remove(new_instance.get()->GetId());
 
-  if (ShouldReuseWebUI(current_entry, dest_url)) {
-    pending_web_ui_.reset();
-    pending_and_current_web_ui_ = web_ui_->AsWeakPtr();
-  } else {
-    SetPendingWebUI(dest_url, bindings);
-    // Make sure the new RenderViewHost has the right bindings.
-    if (pending_web_ui() &&
-        !render_frame_host_->GetProcess()->IsForGuestsOnly()) {
-      render_frame_host_->render_view_host()->AllowBindings(
-          pending_web_ui()->GetBindings());
-    }
-  }
-
-  if (pending_web_ui() && render_frame_host_->IsRenderFrameLive()) {
-    pending_web_ui()->RenderViewReused(render_frame_host_->render_view_host(),
-                                       frame_tree_node_->IsMainFrame());
-  }
+  UpdateWebUIOnCurrentFrameHost(dest_url, dest_is_restore, bindings);
 
   // The renderer can exit view source mode when any error or cancellation
   // happen. We must overwrite to recover the mode.
   if (dest_is_view_source_mode) {
     render_frame_host_->render_view_host()->Send(
         new ViewMsg_EnableViewSourceMode(
             render_frame_host_->render_view_host()->GetRoutingID()));
   }
 
   return render_frame_host_.get();
 }
 
+void RenderFrameHostManager::UpdateWebUIOnCurrentFrameHost(const GURL& dest_url,
+                                                           bool dest_is_restore,
+                                                           int bindings) {
+  WebUI::TypeID previous_web_ui_type = render_frame_host_->web_ui_type();
+  bool changed_web_ui = render_frame_host_->UpdateWebUI(dest_url, bindings);
+
+  // If a change in WebUI happened, check this is an acceptable case.
+  if (changed_web_ui)
+    CheckWebUITransition(previous_web_ui_type, dest_url, dest_is_restore);
+
+  // If there is a WebUI in the current RenderFrameHost, it will navigate.
+  current_web_ui_is_navigating_ = !!render_frame_host_->web_ui();
+  DCHECK_EQ(GetNavigatingWebUI(), render_frame_host_->web_ui());
+
+  // If the current RenderFrameHost has a WebUI and the associated RenderFrame
+  // is alive, notify to the WebUI that the RenderView is being created or
+  // reused depending on whether the WebUI was changed or not.
+  if (GetNavigatingWebUI() && render_frame_host_->IsRenderFrameLive()) {
+    if (changed_web_ui) {
+      GetNavigatingWebUI()->RenderViewCreated(
+          render_frame_host_->render_view_host());
+    } else {
+      GetNavigatingWebUI()->RenderViewReused(
+          render_frame_host_->render_view_host(),
+          frame_tree_node_->IsMainFrame());
+    }
+  }
+}
+
 void RenderFrameHostManager::CancelPending() {
   TRACE_EVENT1("navigation", "RenderFrameHostManager::CancelPending",
                "FrameTreeNode id", frame_tree_node_->frame_tree_node_id());
+  current_web_ui_is_navigating_ = false;
   DiscardUnusedFrame(UnsetPendingRenderFrameHost());
 }
 
 scoped_ptr<RenderFrameHostImpl>
 RenderFrameHostManager::UnsetPendingRenderFrameHost() {
   scoped_ptr<RenderFrameHostImpl> pending_render_frame_host =
       pending_render_frame_host_.Pass();
 
   RenderFrameDevToolsAgentHost::OnCancelPendingNavigation(
       pending_render_frame_host.get(),
       render_frame_host_.get());
 
+  current_web_ui_is_navigating_ = false;
+
   // We no longer need to prevent the process from exiting.
   pending_render_frame_host->GetProcess()->RemovePendingView();
 
-  pending_web_ui_.reset();
-  pending_and_current_web_ui_.reset();
-
   return pending_render_frame_host.Pass();
 }
 
 scoped_ptr<RenderFrameHostImpl> RenderFrameHostManager::SetRenderFrameHost(
     scoped_ptr<RenderFrameHostImpl> render_frame_host) {
   // Swap the two.
   scoped_ptr<RenderFrameHostImpl> old_render_frame_host =
       render_frame_host_.Pass();
   render_frame_host_ = render_frame_host.Pass();
 
@@ skipping 154 matching lines @@
     if (rvh && !rvh->IsRenderViewLive()) {
       EnsureRenderViewInitialized(rvh, instance);
     } else {
       // Create a swapped out RenderView in the given SiteInstance if none
       // exists. Since an opener can point to a subframe, do this on the root
       // frame of the current opener's frame tree.
       if (SiteIsolationPolicy::IsSwappedOutStateForbidden()) {
         frame_tree->root()->render_manager()->CreateRenderFrameProxy(instance);
       } else {
         frame_tree->root()->render_manager()->CreateRenderFrame(
-            instance, nullptr, CREATE_RF_SWAPPED_OUT | CREATE_RF_HIDDEN,
-            nullptr);
+            instance, CREATE_RF_SWAPPED_OUT | CREATE_RF_HIDDEN, nullptr);
       }
     }
   }
 }
 
 int RenderFrameHostManager::GetOpenerRoutingID(SiteInstance* instance) {
   if (!frame_tree_node_->opener())
     return MSG_ROUTING_NONE;
 
   return frame_tree_node_->opener()
       ->render_manager()
       ->GetRoutingIdForSiteInstance(instance);
 }
 
+void RenderFrameHostManager::CheckWebUITransition(
+    WebUI::TypeID previous_web_ui_type,
+    const GURL& dest_url,
+    bool dest_is_restore) {
+  // There are a few navigation cases that allow for changes to the WebUI of
+  // the current RenderFrameHost.
+  BrowserContext* browser_context =
+      delegate_->GetControllerForRenderManager().GetBrowserContext();
+  if (render_frame_host_->web_ui()) {
+    // Switching WebUI from one type to another while keeping the
+    // RenderFrameHost is never acceptable.
+    CHECK(previous_web_ui_type == WebUI::kNoWebUI);
+
+    // Going from not having to having a WebUI is acceptable for:
+    // - The first navigation of this frame.
+    const NavigationEntry* current_entry =
+        delegate_->GetLastCommittedNavigationEntryForRenderManager();
+    bool is_first_navigation_for_frame = !current_entry;
+
+    // - A restore navigation to a WebUI URL.
+    const GURL& current_effective_url =
+        current_entry ? SiteInstanceImpl::GetEffectiveURL(
+                            browser_context, current_entry->GetURL())
+                      : render_frame_host_->GetSiteInstance()->GetSiteURL();
+    bool is_webui_restore =
+        dest_is_restore &&
+        WebUIControllerFactoryRegistry::GetInstance()->UseWebUIForURL(
+            browser_context, current_effective_url);
+
+    // - Navigating back from a special renderer URL.
+    bool is_back_from_renderer_url =
+        current_entry && IsRendererDebugURL(current_entry->GetURL());
+
+    // - Navigating in webview tag guest.
+    bool is_webview_tag_guest =
+        render_frame_host_->GetSiteInstance()->GetSiteURL().SchemeIs(
+            kGuestScheme);
+    CHECK(is_first_navigation_for_frame || is_webui_restore ||
+          is_back_from_renderer_url || is_webview_tag_guest);
+  } else {
+    // Going from having to not having a WebUI is acceptable when Navigating to
+    // a special renderer URL.
+    CHECK(IsRendererDebugURL(
+        SiteInstanceImpl::GetEffectiveURL(browser_context, dest_url)));
+  }
+}
+
 }  // namespace content