GuestView: Move lifetime management out of content

This CL introduces an internal destroyGuest API, and enables preservation of
guests when display:none is set.

This patch is also a big step towards guest teleportation.

BUG=419020, 330264
TBR=kenrb@chromium.org for browser_plugin_messages.h IPC removal, asvitkine@chromium.org for histograms.xml

Review URL: https://codereview.chromium.org/618823002

Cr-Commit-Position: refs/heads/master@{#297751}

33 files changed, 313 insertions, 282 deletions

diff --git a/chrome/browser/apps/web_view_browsertest.cc b/chrome/browser/apps/web_view_browsertest.cc
index 0a39ca9..491a90b 100644
--- a/chrome/browser/apps/web_view_browsertest.cc
+++ b/chrome/browser/apps/web_view_browsertest.cc
@@ -819,33 +819,6 @@ IN_PROC_BROWSER_TEST_F(WebViewTest, AutoSize) {
       << message_;
 }
 
-// Tests that a <webview> that is set to "display: none" after load and then
-// setting "display: block" re-renders the plugin properly.
-//
-// Initially after loading the <webview> and the test sets <webview> to
-// "display: none".
-// This causes the browser plugin to be destroyed, we then set the
-// style.display of the <webview> to block again and check that loadstop
-// fires properly.
-IN_PROC_BROWSER_TEST_F(WebViewTest, DisplayNoneAndBack) {
-  LoadAppWithGuest("web_view/display_none_and_back");
-
-  scoped_refptr<content::MessageLoopRunner> loop_runner(
-      new content::MessageLoopRunner);
-  WebContentsHiddenObserver observer(GetGuestWebContents(),
-                                     loop_runner->QuitClosure());
-
-  // Handled in platform_apps/web_view/display_none_and_back/main.js
-  SendMessageToEmbedder("hide-guest");
-  GetGuestViewManager()->WaitForGuestDeleted();
-  ExtensionTestMessageListener test_passed_listener("WebViewTest.PASSED",
-                                                    false);
-
-  SendMessageToEmbedder("show-guest");
-  GetGuestViewManager()->WaitForGuestCreated();
-  EXPECT_TRUE(test_passed_listener.WaitUntilSatisfied());
-}
-
 // http://crbug.com/326332
 IN_PROC_BROWSER_TEST_F(WebViewTest, DISABLED_Shim_TestAutosizeAfterNavigation) {
   TestHelper("testAutosizeAfterNavigation", "web_view/shim", NO_TEST_SERVER);
diff --git a/chrome/renderer/resources/extensions/app_view.js b/chrome/renderer/resources/extensions/app_view.js
index 968340b..0b16e65 100644
--- a/chrome/renderer/resources/extensions/app_view.js
+++ b/chrome/renderer/resources/extensions/app_view.js
@@ -11,6 +11,8 @@ var guestViewInternalNatives = requireNative('guest_view_internal');
 function AppViewInternal(appviewNode) {
   privates(appviewNode).internal = this;
   this.appviewNode = appviewNode;
+  this.elementAttached = false;
+  this.pendingGuestCreation = false;
 
   this.browserPluginNode = this.createBrowserPluginNode();
   var shadowRoot = this.appviewNode.createShadowRoot();
@@ -41,15 +43,25 @@ AppViewInternal.prototype.createBrowserPluginNode = function() {
 };
 
 AppViewInternal.prototype.connect = function(app, data, callback) {
+  if (!this.elementAttached || this.pendingGuestCreation) {
+    if (callback) {
+      callback(false);
+    }
+    return;
+  }
   var createParams = {
     'appId': app,
     'data': data || {}
   };
-  var self = this;
   GuestViewInternal.createGuest(
     'appview',
     createParams,
     function(guestInstanceId) {
+      this.pendingGuestCreation = false;
+      if (guestInstanceId && !this.elementAttached) {
+        GuestViewInternal.destroyGuest(guestInstanceId);
+        guestInstanceId = 0;
+      }
       if (!guestInstanceId) {
         this.browserPluginNode.style.visibility = 'hidden';
         var errorMsg = 'Unable to connect to app "' + app + '".';
@@ -66,20 +78,50 @@ AppViewInternal.prototype.connect = function(app, data, callback) {
       }
     }.bind(this)
   );
+  this.pendingGuestCreation = true;
 };
 
 AppViewInternal.prototype.attachWindow = function(guestInstanceId) {
   this.guestInstanceId = guestInstanceId;
+  if (!this.internalInstanceId) {
+    return;
+  }
   var params = {
-    'instanceId': this.viewInstanceId,
+    'instanceId': this.viewInstanceId
   };
   this.browserPluginNode.style.visibility = 'visible';
   return guestViewInternalNatives.AttachGuest(
-      parseInt(this.browserPluginNode.getAttribute('internalinstanceid')),
+      this.internalInstanceId,
       guestInstanceId,
       params);
 };
 
+AppViewInternal.prototype.handleBrowserPluginAttributeMutation =
+    function(name, oldValue, newValue) {
+  if (name == 'internalinstanceid' && !oldValue && !!newValue) {
+    this.browserPluginNode.removeAttribute('internalinstanceid');
+    this.internalInstanceId = parseInt(newValue);
+
+    if (!!this.guestInstanceId && this.guestInstanceId != 0) {
+      var params = {
+        'instanceId': this.viewInstanceId
+      };
+      guestViewInternalNatives.AttachGuest(
+          this.internalInstanceId,
+          this.guestInstanceId,
+          params);
+    }
+    return;
+  }
+};
+
+AppViewInternal.prototype.reset = function() {
+  if (this.guestInstanceId) {
+    GuestViewInternal.destroyGuest(this.guestInstanceId);
+    this.guestInstanceId = undefined;
+  }
+};
+
 function registerBrowserPluginElement() {
   var proto = Object.create(HTMLObjectElement.prototype);
 
@@ -94,6 +136,14 @@ function registerBrowserPluginElement() {
     var unused = this.nonExistentAttribute;
   };
 
+  proto.attributeChangedCallback = function(name, oldValue, newValue) {
+    var internal = privates(this).internal;
+    if (!internal) {
+      return;
+    }
+    internal.handleBrowserPluginAttributeMutation(name, oldValue, newValue);
+  };
+
   AppViewInternal.BrowserPlugin =
       DocumentNatives.RegisterElement('appplugin', {extends: 'object',
                                                     prototype: proto});
@@ -111,10 +161,28 @@ function registerAppViewElement() {
     new AppViewInternal(this);
   };
 
+  proto.attachedCallback = function() {
+    var internal = privates(this).internal;
+    if (!internal) {
+      return;
+    }
+    internal.elementAttached = true;
+  };
+
+  proto.detachedCallback = function() {
+    var internal = privates(this).internal;
+    if (!internal) {
+      return;
+    }
+    internal.elementAttached = false;
+    internal.reset();
+  };
+
   proto.connect = function() {
     var internal = privates(this).internal;
     $Function.apply(internal.connect, internal, arguments);
   }
+
   window.AppView =
       DocumentNatives.RegisterElement('appview', {prototype: proto});
 
diff --git a/chrome/renderer/resources/extensions/extension_options.js b/chrome/renderer/resources/extensions/extension_options.js
index 32bee63..38ca845 100644
--- a/chrome/renderer/resources/extensions/extension_options.js
+++ b/chrome/renderer/resources/extensions/extension_options.js
@@ -24,6 +24,9 @@ function ExtensionOptionsInternal(extensionoptionsNode) {
   privates(extensionoptionsNode).internal = this;
   this.extensionoptionsNode = extensionoptionsNode;
   this.viewInstanceId = IdGenerator.GetNextId();
+  this.guestInstanceId = 0;
+  this.elementAttached = false;
+  this.pendingGuestCreation = false;
 
   this.autosizeDeferred = false;
 
@@ -68,7 +71,14 @@ ExtensionOptionsInternal.prototype.createBrowserPluginNode = function() {
   return browserPluginNode;
 };
 
-ExtensionOptionsInternal.prototype.createGuest = function() {
+ExtensionOptionsInternal.prototype.createGuestIfNecessary = function() {
+  if (!this.elementAttached || this.pendingGuestCreation) {
+    return;
+  }
+  if (this.guestInstanceId != 0) {
+    this.attachWindow();
+    return;
+  }
   var params = {
     'extensionId': this.extensionId,
   };
@@ -76,6 +86,11 @@ ExtensionOptionsInternal.prototype.createGuest = function() {
       'extensionoptions',
       params,
       function(guestInstanceId) {
+        this.pendingGuestCreation = false;
+        if (guestInstanceId && !this.elementAttached) {
+          GuestViewInternal.destroyGuest(guestInstanceId);
+          guestInstanceId = 0;
+        }
         if (guestInstanceId == 0) {
           // Fire a createfailed event here rather than in ExtensionOptionsGuest
           // because the guest will not be created, and cannot fire an event.
@@ -86,7 +101,9 @@ ExtensionOptionsInternal.prototype.createGuest = function() {
           this.guestInstanceId = guestInstanceId;
           this.attachWindow();
         }
-      }.bind(this));
+      }.bind(this)
+  );
+  this.pendingGuestCreation = true;
 };
 
 ExtensionOptionsInternal.prototype.dispatchEvent =
@@ -113,7 +130,7 @@ ExtensionOptionsInternal.prototype.handleExtensionOptionsAttributeMutation =
 
     // If a guest view does not exist then create one.
     if (!this.guestInstanceId) {
-      this.createGuest();
+      this.createGuestIfNecessary();
       return;
     }
     // TODO(ericzeng): Implement navigation to another guest view if we want
@@ -142,10 +159,11 @@ ExtensionOptionsInternal.prototype.handleExtensionOptionsAttributeMutation =
 ExtensionOptionsInternal.prototype.handleBrowserPluginAttributeMutation =
     function(name, oldValue, newValue) {
   if (name == 'internalinstanceid' && !oldValue && !!newValue) {
+    this.elementAttached = true;
     this.internalInstanceId = parseInt(newValue);
     this.browserPluginNode.removeAttribute('internalinstanceid');
     if (this.extensionId)
-      this.createGuest();
+      this.createGuestIfNecessary();
 
   }
 };
@@ -293,6 +311,13 @@ ExtensionOptionsInternal.prototype.resumeDeferredAutoSize = function() {
   }
 };
 
+ExtensionOptionsInternal.prototype.reset = function() {
+  if (this.guestInstanceId) {
+    GuestViewInternal.destroyGuest(this.guestInstanceId);
+    this.guestInstanceId = undefined;
+  }
+};
+
 function registerBrowserPluginElement() {
   var proto = Object.create(HTMLObjectElement.prototype);
 
@@ -331,10 +356,20 @@ function registerExtensionOptionsElement() {
     new ExtensionOptionsInternal(this);
   };
 
+  proto.detachedCallback = function() {
+    var internal = privates(this).internal;
+    if (!internal) {
+      return;
+    }
+    internal.elementAttached = false;
+    internal.reset();
+  };
+
   proto.attributeChangedCallback = function(name, oldValue, newValue) {
     var internal = privates(this).internal;
-    if (!internal)
+    if (!internal) {
       return;
+    }
     internal.handleExtensionOptionsAttributeMutation(name, oldValue, newValue);
   };
 
diff --git a/chrome/test/data/extensions/platform_apps/app_view/shim/main.js b/chrome/test/data/extensions/platform_apps/app_view/shim/main.js
index f305dca..fe3c2eb 100644
--- a/chrome/test/data/extensions/platform_apps/app_view/shim/main.js
+++ b/chrome/test/data/extensions/platform_apps/app_view/shim/main.js
@@ -71,11 +71,13 @@ embedder.test.assertFalse = function(condition) {
 function testAppViewWithUndefinedDataShouldSucceed(appToEmbed) {
   var appview = new AppView();
   LOG('appToEmbed  ' + appToEmbed);
+  document.body.appendChild(appview);
   // Step 1: Attempt to connect to a non-existant app.
   LOG('attempting to connect to non-existant app.');
   appview.connect('abc123', undefined, function(success) {
     // Make sure we fail.
     if (success) {
+      LOG('UNEXPECTED CONNECTION.');
       embedder.test.fail();
       return;
     }
@@ -85,44 +87,49 @@ function testAppViewWithUndefinedDataShouldSucceed(appToEmbed) {
     appview.connect(appToEmbed, undefined, function(success) {
       // Make sure we don't fail.
       if (!success) {
+        LOG('FAILED TO CONNECT.');
         embedder.test.fail();
         return;
       }
+      LOG('CONNECTED.');
       embedder.test.succeed();
     });
   });
-  document.body.appendChild(appview);
 };
 
 function testAppViewRefusedDataShouldFail(appToEmbed) {
   var appview = new AppView();
   LOG('appToEmbed  ' + appToEmbed);
+  document.body.appendChild(appview);
   LOG('Attempting to connect to app with refused params.');
   appview.connect(appToEmbed, { 'foo': 'bar' }, function(success) {
     // Make sure we fail.
     if (success) {
+      LOG('UNEXPECTED CONNECTION.');
       embedder.test.fail();
       return;
     }
+    LOG('FAILED TO CONNECT.');
     embedder.test.succeed();
   });
-  document.body.appendChild(appview);
 };
 
 function testAppViewGoodDataShouldSucceed(appToEmbed) {
   var appview = new AppView();
   LOG('appToEmbed  ' + appToEmbed);
+  document.body.appendChild(appview);
   LOG('Attempting to connect to app with good params.');
   // Step 2: Attempt to connect to an app with good params.
   appview.connect(appToEmbed, { 'foo': 'bleep' }, function(success) {
     // Make sure we don't fail.
     if (!success) {
+      LOG('FAILED TO CONNECT.');
       embedder.test.fail();
       return;
     }
+    LOG('CONNECTED.');
     embedder.test.succeed();
   });
-  document.body.appendChild(appview);
 };
 
 embedder.test.testList = {
diff --git a/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/main.html b/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/main.html
deleted file mode 100644
index d7227a6..0000000
--- a/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/main.html
+++ /dev/null
@@ -1,12 +0,0 @@
-<!doctype html>
-<!--
- * 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.
--->
-<html>
-<body>
-  <div id="webview-tag-container"></div>
-  <script src="main.js"></script>
-</body>
-</html>
diff --git a/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/main.js b/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/main.js
deleted file mode 100644
index 6a54e0f..0000000
--- a/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/main.js
+++ /dev/null
@@ -1,49 +0,0 @@
-// 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.
-
-var LOG = function(msg) {
-  window.console.log(msg);
-};
-
-var failTest = function() {
-  chrome.test.sendMessage('WebViewTest.FAILURE');
-};
-
-var firstTime = true;
-
-var startTest = function() {
-  document.querySelector('#webview-tag-container').innerHTML =
-      '<webview style="width: 10px; height: 10px; margin: 0; padding: 0;"' +
-      '></webview>';
-
-  var webview = document.querySelector('webview');
-  var onLoadStop = function(e) {
-    if (firstTime) {
-      firstTime = false;
-      chrome.test.sendMessage('WebViewTest.LAUNCHED');
-    } else {
-      chrome.test.sendMessage('WebViewTest.PASSED');
-    }
-  };
-
-  webview.addEventListener('loadstop', onLoadStop);
-  webview.src = 'data:text/html,<body>Guest</body>';
-};
-
-window.onAppCommand = function(command) {
-  LOG('onAppCommand: ' + command);
-  switch (command) {
-    case 'hide-guest':
-      document.querySelector('webview').style.display = 'none';
-      break;
-    case 'show-guest':
-      document.querySelector('webview').style.display = '';
-      break;
-    default:
-      failTest();
-      break;
-  }
-};
-
-window.onload = startTest;
diff --git a/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/manifest.json b/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/manifest.json
deleted file mode 100644
index 134230f..0000000
--- a/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/manifest.json
+++ /dev/null
@@ -1,12 +0,0 @@
-{
-  "name": "<webview> check display: none toggling.",
-  "version": "1",
-  "permissions": [
-    "webview"
-  ],
-  "app": {
-    "background": {
-      "scripts": ["test.js"]
-    }
-  }
-}
diff --git a/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/test.js b/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/test.js
deleted file mode 100644
index a80d274..0000000
--- a/chrome/test/data/extensions/platform_apps/web_view/display_none_and_back/test.js
+++ /dev/null
@@ -1,7 +0,0 @@
-// 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.
-
-chrome.app.runtime.onLaunched.addListener(function() {
-  chrome.app.window.create('main.html', {}, function () {});
-});
diff --git a/content/browser/browser_plugin/browser_plugin_guest.cc b/content/browser/browser_plugin/browser_plugin_guest.cc
index f2a0f74..1c73384 100644
--- a/content/browser/browser_plugin/browser_plugin_guest.cc
+++ b/content/browser/browser_plugin/browser_plugin_guest.cc
@@ -87,6 +87,7 @@ BrowserPluginGuest::BrowserPluginGuest(bool has_render_view,
       last_text_input_type_(ui::TEXT_INPUT_TYPE_NONE),
       last_input_mode_(ui::TEXT_INPUT_MODE_DEFAULT),
       last_can_compose_inline_(true),
+      guest_proxy_routing_id_(MSG_ROUTING_NONE),
       delegate_(delegate),
       weak_ptr_factory_(this) {
   DCHECK(web_contents);
@@ -134,10 +135,6 @@ bool BrowserPluginGuest::LockMouse(bool allowed) {
   return embedder_web_contents()->GotResponseToLockMouseRequest(allowed);
 }
 
-void BrowserPluginGuest::Destroy() {
-  delegate_->Destroy();
-}
-
 WebContentsImpl* BrowserPluginGuest::CreateNewGuestWindow(
     const WebContents::CreateParams& params) {
   WebContentsImpl* new_contents =
@@ -175,7 +172,6 @@ bool BrowserPluginGuest::OnMessageReceivedFromEmbedder(
     IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_ImeSetComposition,
                         OnImeSetComposition)
     IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_LockMouse_ACK, OnLockMouseAck)
-    IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_PluginDestroyed, OnPluginDestroyed)
     IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_ReclaimCompositorResources,
                         OnReclaimCompositorResources)
     IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_ResizeGuest, OnResizeGuest)
@@ -200,13 +196,15 @@ void BrowserPluginGuest::Initialize(
   guest_window_rect_ = gfx::Rect(params.origin,
                                  params.resize_guest_params.view_size);
 
+  WebContentsViewGuest* new_view =
+      static_cast<WebContentsViewGuest*>(GetWebContents()->GetView());
+  if (attached())
+    new_view->OnGuestDetached(embedder_web_contents_->GetView());
+
   // Once a BrowserPluginGuest has an embedder WebContents, it's considered to
   // be attached.
   embedder_web_contents_ = embedder_web_contents;
-
-  WebContentsViewGuest* new_view =
-      static_cast<WebContentsViewGuest*>(GetWebContents()->GetView());
-  new_view->OnGuestInitialized(embedder_web_contents->GetView());
+  new_view->OnGuestAttached(embedder_web_contents->GetView());
 
   RendererPreferences* renderer_prefs =
       GetWebContents()->GetMutableRendererPrefs();
@@ -336,7 +334,6 @@ void BrowserPluginGuest::SwapCompositorFrame(
   guest_params.output_surface_id = output_surface_id;
   guest_params.producing_route_id = host_routing_id;
   guest_params.producing_host_id = host_process_id;
-
   SendMessageToEmbedder(
       new BrowserPluginMsg_CompositorFrameSwapped(
           browser_plugin_instance_id(), guest_params));
@@ -454,7 +451,6 @@ bool BrowserPluginGuest::ShouldForwardToBrowserPluginGuest(
     case BrowserPluginHostMsg_ImeConfirmComposition::ID:
     case BrowserPluginHostMsg_ImeSetComposition::ID:
     case BrowserPluginHostMsg_LockMouse_ACK::ID:
-    case BrowserPluginHostMsg_PluginDestroyed::ID:
     case BrowserPluginHostMsg_ReclaimCompositorResources::ID:
     case BrowserPluginHostMsg_ResizeGuest::ID:
     case BrowserPluginHostMsg_SetEditCommandsForNextKeyEvent::ID:
@@ -520,20 +516,21 @@ void BrowserPluginGuest::Attach(
     int browser_plugin_instance_id,
     WebContentsImpl* embedder_web_contents,
     const BrowserPluginHostMsg_Attach_Params& params) {
-  if (attached())
-    return;
-
   delegate_->WillAttach(embedder_web_contents, browser_plugin_instance_id);
 
   // If a RenderView has already been created for this new window, then we need
   // to initialize the browser-side state now so that the RenderFrameHostManager
   // does not create a new RenderView on navigation.
   if (has_render_view_) {
+    // This will trigger a callback to RenderViewReady after a round-trip IPC.
     static_cast<RenderViewHostImpl*>(
         GetWebContents()->GetRenderViewHost())->Init();
-    WebContentsViewGuest* new_view =
+    WebContentsViewGuest* web_contents_view =
         static_cast<WebContentsViewGuest*>(GetWebContents()->GetView());
-    new_view->CreateViewForWidget(web_contents()->GetRenderViewHost());
+    if (!web_contents()->GetRenderViewHost()->GetView()) {
+      web_contents_view->CreateViewForWidget(
+          web_contents()->GetRenderViewHost());
+    }
   }
 
   Initialize(browser_plugin_instance_id, params, embedder_web_contents);
@@ -542,11 +539,18 @@ void BrowserPluginGuest::Attach(
 
   // Create a swapped out RenderView for the guest in the embedder render
   // process, so that the embedder can access the guest's window object.
-  int guest_routing_id =
-      GetWebContents()->CreateSwappedOutRenderView(
-          embedder_web_contents_->GetSiteInstance());
+  // On reattachment, we can reuse the same swapped out RenderView because
+  // the embedder process will always be the same even if the embedder
+  // WebContents changes.
+  if (guest_proxy_routing_id_ == MSG_ROUTING_NONE) {
+    guest_proxy_routing_id_ =
+        GetWebContents()->CreateSwappedOutRenderView(
+            embedder_web_contents_->GetSiteInstance());
+  }
+
+  delegate_->DidAttach(guest_proxy_routing_id_);
 
-  delegate_->DidAttach(guest_routing_id);
+  has_render_view_ = true;
 
   RecordAction(base::UserMetricsAction("BrowserPlugin.Guest.Attached"));
 }
@@ -660,10 +664,6 @@ void BrowserPluginGuest::OnLockMouseAck(int browser_plugin_instance_id,
     mouse_locked_ = true;
 }
 
-void BrowserPluginGuest::OnPluginDestroyed(int browser_plugin_instance_id) {
-  Destroy();
-}
-
 void BrowserPluginGuest::OnResizeGuest(
     int browser_plugin_instance_id,
     const BrowserPluginHostMsg_ResizeGuest_Params& params) {
diff --git a/content/browser/browser_plugin/browser_plugin_guest.h b/content/browser/browser_plugin/browser_plugin_guest.h
index cecca6d..c6b7fb7 100644
--- a/content/browser/browser_plugin/browser_plugin_guest.h
+++ b/content/browser/browser_plugin/browser_plugin_guest.h
@@ -114,10 +114,6 @@ class CONTENT_EXPORT BrowserPluginGuest : public WebContentsObserver {
   // Called when the embedder WebContents changes visibility.
   void EmbedderVisibilityChanged(bool visible);
 
-  // Destroys the guest WebContents and all its associated state, including
-  // this BrowserPluginGuest, and its new unattached windows.
-  void Destroy();
-
   // Creates a new guest WebContentsImpl with the provided |params| with |this|
   // as the |opener|.
   WebContentsImpl* CreateNewGuestWindow(
@@ -253,7 +249,6 @@ class CONTENT_EXPORT BrowserPluginGuest : public WebContentsObserver {
                    bool last_unlocked_by_target,
                    bool privileged);
   void OnLockMouseAck(int instance_id, bool succeeded);
-  void OnPluginDestroyed(int instance_id);
   // Resizes the guest's web contents.
   void OnResizeGuest(
       int instance_id, const BrowserPluginHostMsg_ResizeGuest_Params& params);
@@ -365,6 +360,10 @@ class CONTENT_EXPORT BrowserPluginGuest : public WebContentsObserver {
   ui::TextInputMode last_input_mode_;
   bool last_can_compose_inline_;
 
+  // The is the routing ID for a swapped out RenderView for the guest
+  // WebContents in the embedder's process.
+  int guest_proxy_routing_id_;
+
   // This is a queue of messages that are destined to be sent to the embedder
   // once the guest is attached to a particular embedder.
   std::deque<linked_ptr<IPC::Message> > pending_messages_;
diff --git a/content/browser/web_contents/web_contents_view_guest.cc b/content/browser/web_contents/web_contents_view_guest.cc
index efa92bd..17a5c484 100644
--- a/content/browser/web_contents/web_contents_view_guest.cc
+++ b/content/browser/web_contents/web_contents_view_guest.cc
@@ -60,7 +60,7 @@ gfx::NativeWindow WebContentsViewGuest::GetTopLevelNativeWindow() const {
   return guest_->embedder_web_contents()->GetTopLevelNativeWindow();
 }
 
-void WebContentsViewGuest::OnGuestInitialized(WebContentsView* parent_view) {
+void WebContentsViewGuest::OnGuestAttached(WebContentsView* parent_view) {
 #if defined(USE_AURA)
   // In aura, ScreenPositionClient doesn't work properly if we do
   // not have the native view associated with this WebContentsViewGuest in the
@@ -71,6 +71,13 @@ void WebContentsViewGuest::OnGuestInitialized(WebContentsView* parent_view) {
 #endif  // defined(USE_AURA)
 }
 
+void WebContentsViewGuest::OnGuestDetached(WebContentsView* old_parent_view) {
+#if defined(USE_AURA)
+  old_parent_view->GetNativeView()->RemoveChild(
+      platform_view_->GetNativeView());
+#endif  // defined(USE_AURA)
+}
+
 ContextMenuParams WebContentsViewGuest::ConvertContextMenuParams(
     const ContextMenuParams& params) const {
   // We need to add |offset| of the guest from the embedder to position the
@@ -143,12 +150,9 @@ RenderWidgetHostViewBase* WebContentsViewGuest::CreateViewForWidget(
   RenderWidgetHostViewBase* platform_widget =
       platform_view_->CreateViewForWidget(render_widget_host);
 
-  RenderWidgetHostViewBase* view = new RenderWidgetHostViewGuest(
-      render_widget_host,
-      guest_,
-      platform_widget);
-
-  return view;
+  return new RenderWidgetHostViewGuest(render_widget_host,
+                                       guest_,
+                                       platform_widget);
 }
 
 RenderWidgetHostViewBase* WebContentsViewGuest::CreateViewForPopupWidget(
diff --git a/content/browser/web_contents/web_contents_view_guest.h b/content/browser/web_contents/web_contents_view_guest.h
index 9a54375..c8b662a 100644
--- a/content/browser/web_contents/web_contents_view_guest.h
+++ b/content/browser/web_contents/web_contents_view_guest.h
@@ -35,7 +35,9 @@ class WebContentsViewGuest : public WebContentsView,
 
   WebContents* web_contents();
 
-  void OnGuestInitialized(WebContentsView* parent_view);
+  void OnGuestAttached(WebContentsView* parent_view);
+
+  void OnGuestDetached(WebContentsView* old_parent_view);
 
   // Converts the guest specific coordinates in |params| to embedder specific
   // ones.
diff --git a/content/common/browser_plugin/browser_plugin_messages.h b/content/common/browser_plugin/browser_plugin_messages.h
index 80c8e23..aaeae27 100644
--- a/content/common/browser_plugin/browser_plugin_messages.h
+++ b/content/common/browser_plugin/browser_plugin_messages.h
@@ -125,11 +125,6 @@ IPC_MESSAGE_ROUTED2(BrowserPluginHostMsg_ReclaimCompositorResources,
                     int /* browser_plugin_instance_id */,
                     FrameHostMsg_ReclaimCompositorResources_Params /* params */)
 
-// When a BrowserPlugin has been removed from the embedder's DOM, it informs
-// the browser process to cleanup the guest.
-IPC_MESSAGE_ROUTED1(BrowserPluginHostMsg_PluginDestroyed,
-                    int /* browser_plugin_instance_id */)
-
 // Tells the guest it has been shown or hidden.
 IPC_MESSAGE_ROUTED2(BrowserPluginHostMsg_SetVisibility,
                     int /* browser_plugin_instance_id */,
diff --git a/content/public/browser/browser_plugin_guest_delegate.h b/content/public/browser/browser_plugin_guest_delegate.h
index 0b7372f5..21e115a 100644
--- a/content/public/browser/browser_plugin_guest_delegate.h
+++ b/content/public/browser/browser_plugin_guest_delegate.h
@@ -57,10 +57,6 @@ class CONTENT_EXPORT BrowserPluginGuestDelegate {
       bool last_unlocked_by_target,
       const base::Callback<void(bool)>& callback) {}
 
-  // Requests that the delegate destroy itself along with its associated
-  // WebContents.
-  virtual void Destroy() {}
-
   // Registers a |callback| with the delegate that the delegate would call when
   // it is about to be destroyed.
   typedef base::Callback<void()> DestructionCallback;
diff --git a/content/renderer/browser_plugin/browser_plugin.cc b/content/renderer/browser_plugin/browser_plugin.cc
index b51b452..7e91f85 100644
--- a/content/renderer/browser_plugin/browser_plugin.cc
+++ b/content/renderer/browser_plugin/browser_plugin.cc
@@ -83,13 +83,6 @@ BrowserPlugin::BrowserPlugin(RenderViewImpl* render_view,
 
 BrowserPlugin::~BrowserPlugin() {
   browser_plugin_manager()->RemoveBrowserPlugin(browser_plugin_instance_id_);
-
-  if (!ready())
-    return;
-
-  browser_plugin_manager()->Send(
-      new BrowserPluginHostMsg_PluginDestroyed(render_view_routing_id_,
-                                               browser_plugin_instance_id_));
 }
 
 bool BrowserPlugin::OnMessageReceived(const IPC::Message& message) {
@@ -174,7 +167,6 @@ void BrowserPlugin::OnCompositorFrameSwapped(const IPC::Message& message) {
   BrowserPluginMsg_CompositorFrameSwapped::Param param;
   if (!BrowserPluginMsg_CompositorFrameSwapped::Read(&message, &param))
     return;
-
   // Note that there is no need to send ACK for this message.
   // If the guest has updated pixels then it is no longer crashed.
   guest_crashed_ = false;
@@ -317,6 +309,8 @@ bool BrowserPlugin::initialize(WebPluginContainer* container) {
 
   g_plugin_container_map.Get().insert(std::make_pair(container_, this));
 
+  browser_plugin_manager()->AddBrowserPlugin(browser_plugin_instance_id_, this);
+
   // This is a way to notify observers of our attributes that this plugin is
   // available in render tree.
   // TODO(lazyboy): This should be done through the delegate instead. Perhaps
@@ -324,7 +318,6 @@ bool BrowserPlugin::initialize(WebPluginContainer* container) {
   UpdateDOMAttribute("internalinstanceid",
                      base::IntToString(browser_plugin_instance_id_));
 
-  browser_plugin_manager()->AddBrowserPlugin(browser_plugin_instance_id_, this);
   return true;
 }
 
diff --git a/content/renderer/browser_plugin/browser_plugin_browsertest.cc b/content/renderer/browser_plugin/browser_plugin_browsertest.cc
index 6abede3..bb0719f 100644
--- a/content/renderer/browser_plugin/browser_plugin_browsertest.cc
+++ b/content/renderer/browser_plugin/browser_plugin_browsertest.cc
@@ -31,9 +31,6 @@ const char kHTMLForBrowserPluginObject[] =
     " src='foo' type='%s'></object>"
     "<script>document.querySelector('object').nonExistentAttribute;</script>";
 
-const char kHTMLForSourcelessPluginObject[] =
-    "<object id='browserplugin' width='640px' height='480px' type='%s'>";
-
 std::string GetHTMLForBrowserPluginObject() {
   return base::StringPrintf(kHTMLForBrowserPluginObject,
                             kBrowserPluginMimeType);
@@ -173,33 +170,4 @@ TEST_F(BrowserPluginTest, InitialResize) {
   ASSERT_TRUE(browser_plugin);
 }
 
-TEST_F(BrowserPluginTest, RemovePlugin) {
-  LoadHTML(GetHTMLForBrowserPluginObject().c_str());
-  MockBrowserPlugin* browser_plugin = GetCurrentPlugin();
-  ASSERT_TRUE(browser_plugin);
-
-  EXPECT_FALSE(browser_plugin_manager()->sink().GetUniqueMessageMatching(
-      BrowserPluginHostMsg_PluginDestroyed::ID));
-  ExecuteJavaScript("x = document.getElementById('browserplugin'); "
-                    "x.parentNode.removeChild(x);");
-  ProcessPendingMessages();
-  EXPECT_TRUE(browser_plugin_manager()->sink().GetUniqueMessageMatching(
-      BrowserPluginHostMsg_PluginDestroyed::ID));
-}
-
-// This test verifies that PluginDestroyed messages do not get sent from a
-// BrowserPlugin that has never navigated.
-TEST_F(BrowserPluginTest, RemovePluginBeforeNavigation) {
-  std::string html = base::StringPrintf(kHTMLForSourcelessPluginObject,
-                                        kBrowserPluginMimeType);
-  LoadHTML(html.c_str());
-  EXPECT_FALSE(browser_plugin_manager()->sink().GetUniqueMessageMatching(
-      BrowserPluginHostMsg_PluginDestroyed::ID));
-  ExecuteJavaScript("x = document.getElementById('browserplugin'); "
-                    "x.parentNode.removeChild(x);");
-  ProcessPendingMessages();
-  EXPECT_FALSE(browser_plugin_manager()->sink().GetUniqueMessageMatching(
-      BrowserPluginHostMsg_PluginDestroyed::ID));
-}
-
 }  // namespace content
diff --git a/extensions/browser/api/guest_view/guest_view_internal_api.cc b/extensions/browser/api/guest_view/guest_view_internal_api.cc
index 37109dc..a397176 100644
--- a/extensions/browser/api/guest_view/guest_view_internal_api.cc
+++ b/extensions/browser/api/guest_view/guest_view_internal_api.cc
@@ -65,6 +65,27 @@ void GuestViewInternalCreateGuestFunction::CreateGuestCallback(
   SendResponse(true);
 }
 
+GuestViewInternalDestroyGuestFunction::
+    GuestViewInternalDestroyGuestFunction() {
+}
+
+GuestViewInternalDestroyGuestFunction::
+    ~GuestViewInternalDestroyGuestFunction() {
+}
+
+bool GuestViewInternalDestroyGuestFunction::RunAsync() {
+  scoped_ptr<guest_view_internal::DestroyGuest::Params> params(
+      guest_view_internal::DestroyGuest::Params::Create(*args_));
+  EXTENSION_FUNCTION_VALIDATE(params.get());
+  GuestViewBase* guest = GuestViewBase::From(
+      render_view_host()->GetProcess()->GetID(), params->instance_id);
+  if (!guest)
+    return false;
+  guest->Destroy();
+  SendResponse(true);
+  return true;
+}
+
 GuestViewInternalSetAutoSizeFunction::
     GuestViewInternalSetAutoSizeFunction() {
 }
diff --git a/extensions/browser/api/guest_view/guest_view_internal_api.h b/extensions/browser/api/guest_view/guest_view_internal_api.h
index d6d54ce..13d7a42 100644
--- a/extensions/browser/api/guest_view/guest_view_internal_api.h
+++ b/extensions/browser/api/guest_view/guest_view_internal_api.h
@@ -24,6 +24,21 @@ class GuestViewInternalCreateGuestFunction : public AsyncExtensionFunction {
   DISALLOW_COPY_AND_ASSIGN(GuestViewInternalCreateGuestFunction);
 };
 
+class GuestViewInternalDestroyGuestFunction : public AsyncExtensionFunction {
+ public:
+  DECLARE_EXTENSION_FUNCTION("guestViewInternal.destroyGuest",
+                             GUESTVIEWINTERNAL_DESTROYGUEST);
+  GuestViewInternalDestroyGuestFunction();
+
+ protected:
+  virtual ~GuestViewInternalDestroyGuestFunction();
+  virtual bool RunAsync() OVERRIDE FINAL;
+
+ private:
+  void DestroyGuestCallback(content::WebContents* guest_web_contents);
+  DISALLOW_COPY_AND_ASSIGN(GuestViewInternalDestroyGuestFunction);
+};
+
 class GuestViewInternalSetAutoSizeFunction : public AsyncExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("guestViewInternal.setAutoSize",
diff --git a/extensions/browser/api/web_view/web_view_internal_api.cc b/extensions/browser/api/web_view/web_view_internal_api.cc
index c6ed1ce..62b3497 100644
--- a/extensions/browser/api/web_view/web_view_internal_api.cc
+++ b/extensions/browser/api/web_view/web_view_internal_api.cc
@@ -65,7 +65,7 @@ bool WebViewInternalNavigateFunction::RunAsyncSafe(WebViewGuest* guest) {
       webview::Navigate::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   std::string src = params->src;
-  guest->NavigateGuest(src);
+  guest->NavigateGuest(src, true /* force_navigation */);
   return true;
 }
 
diff --git a/extensions/browser/extension_function_histogram_value.h b/extensions/browser/extension_function_histogram_value.h
index e46694e..a524997 100644
--- a/extensions/browser/extension_function_histogram_value.h
+++ b/extensions/browser/extension_function_histogram_value.h
@@ -958,6 +958,7 @@ enum HistogramValue {
   HOTWORDPRIVATE_GETLAUNCHSTATE,
   HOTWORDPRIVATE_SETHOTWORDALWAYSONSEARCHENABLED,
   WEBVIEWINTERNAL_LOADDATAWITHBASEURL,
+  GUESTVIEWINTERNAL_DESTROYGUEST,
   // Last entry: Add new entries above and ensure to update
   // tools/metrics/histograms/histograms.xml.
   ENUM_BOUNDARY
diff --git a/extensions/browser/guest_view/app_view/app_view_guest.cc b/extensions/browser/guest_view/app_view/app_view_guest.cc
index e608a49..92608ac 100644
--- a/extensions/browser/guest_view/app_view/app_view_guest.cc
+++ b/extensions/browser/guest_view/app_view/app_view_guest.cc
@@ -203,8 +203,12 @@ void AppViewGuest::DidAttachToEmbedder() {
   // element. This means that the host element knows how to route input
   // events to the guest, and the guest knows how to get frames to the
   // embedder.
+  if (!url_.is_valid())
+    return;
+
   web_contents()->GetController().LoadURL(
       url_, content::Referrer(), ui::PAGE_TRANSITION_LINK, std::string());
+  url_ = GURL();
 }
 
 void AppViewGuest::DidInitialize() {
diff --git a/extensions/browser/guest_view/extension_options/extension_options_guest.cc b/extensions/browser/guest_view/extension_options/extension_options_guest.cc
index 32b5dce..ef79ee7 100644
--- a/extensions/browser/guest_view/extension_options/extension_options_guest.cc
+++ b/extensions/browser/guest_view/extension_options/extension_options_guest.cc
@@ -40,7 +40,8 @@ ExtensionOptionsGuest::ExtensionOptionsGuest(
     : GuestView<ExtensionOptionsGuest>(browser_context, guest_instance_id),
       extension_options_guest_delegate_(
           extensions::ExtensionsAPIClient::Get()
-              ->CreateExtensionOptionsGuestDelegate(this)) {
+              ->CreateExtensionOptionsGuestDelegate(this)),
+      has_navigated_(false) {
 }
 
 ExtensionOptionsGuest::~ExtensionOptionsGuest() {
@@ -108,10 +109,16 @@ void ExtensionOptionsGuest::CreateWebContents(
 
 void ExtensionOptionsGuest::DidAttachToEmbedder() {
   SetUpAutoSize();
+
+  // We should not re-navigate on reattachment.
+  if (has_navigated_)
+    return;
+
   web_contents()->GetController().LoadURL(options_page_,
                                           content::Referrer(),
                                           ui::PAGE_TRANSITION_LINK,
                                           std::string());
+  has_navigated_ = true;
 }
 
 void ExtensionOptionsGuest::DidInitialize() {
diff --git a/extensions/browser/guest_view/extension_options/extension_options_guest.h b/extensions/browser/guest_view/extension_options/extension_options_guest.h
index 6d9f9e5..73b28ef 100644
--- a/extensions/browser/guest_view/extension_options/extension_options_guest.h
+++ b/extensions/browser/guest_view/extension_options/extension_options_guest.h
@@ -77,6 +77,7 @@ class ExtensionOptionsGuest
   scoped_ptr<extensions::ExtensionOptionsGuestDelegate>
       extension_options_guest_delegate_;
   GURL options_page_;
+  bool has_navigated_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionOptionsGuest);
 };
diff --git a/extensions/browser/guest_view/guest_view_base.cc b/extensions/browser/guest_view/guest_view_base.cc
index 9f5a244..6a181a6 100644
--- a/extensions/browser/guest_view/guest_view_base.cc
+++ b/extensions/browser/guest_view/guest_view_base.cc
@@ -70,16 +70,18 @@ class GuestViewBase::EmbedderWebContentsObserver : public WebContentsObserver {
 
   // WebContentsObserver implementation.
   virtual void WebContentsDestroyed() OVERRIDE {
+    // If the embedder is destroyed then destroy the guest.
     Destroy();
   }
 
-  virtual void RenderViewHostChanged(
-      content::RenderViewHost* old_host,
-      content::RenderViewHost* new_host) OVERRIDE {
+  virtual void AboutToNavigateRenderView(
+      content::RenderViewHost* render_view_host) OVERRIDE {
+    // If the embedder navigates then destroy the guest.
     Destroy();
   }
 
   virtual void RenderProcessGone(base::TerminationStatus status) OVERRIDE {
+    // If the embedder crashes, then destroy the guest.
     Destroy();
   }
 
@@ -297,24 +299,6 @@ void GuestViewBase::RenderProcessExited(content::RenderProcessHost* host,
   Destroy();
 }
 
-void GuestViewBase::Destroy() {
-  DCHECK(web_contents());
-  content::RenderProcessHost* host =
-      content::RenderProcessHost::FromID(embedder_render_process_id());
-  if (host)
-    host->RemoveObserver(this);
-  WillDestroy();
-  if (!destruction_callback_.is_null())
-    destruction_callback_.Run();
-
-  webcontents_guestview_map.Get().erase(web_contents());
-  GuestViewManager::FromBrowserContext(browser_context_)->
-      RemoveGuest(guest_instance_id_);
-  pending_events_.clear();
-
-  delete web_contents();
-}
-
 void GuestViewBase::DidAttach(int guest_proxy_routing_id) {
   // Give the derived class an opportunity to perform some actions.
   DidAttachToEmbedder();
@@ -341,6 +325,28 @@ void GuestViewBase::GuestSizeChanged(const gfx::Size& old_size,
   GuestSizeChangedDueToAutoSize(old_size, new_size);
 }
 
+void GuestViewBase::Destroy() {
+  DCHECK(web_contents());
+  content::RenderProcessHost* host =
+      content::RenderProcessHost::FromID(embedder_render_process_id());
+  if (host)
+    host->RemoveObserver(this);
+
+  // Give the derived class an opportunity to perform some cleanup.
+  WillDestroy();
+
+  // Give the content module an opportunity to perform some cleanup.
+  if (!destruction_callback_.is_null())
+    destruction_callback_.Run();
+
+  webcontents_guestview_map.Get().erase(web_contents());
+  GuestViewManager::FromBrowserContext(browser_context_)->
+      RemoveGuest(guest_instance_id_);
+  pending_events_.clear();
+
+  delete web_contents();
+}
+
 void GuestViewBase::SetAttachParams(const base::DictionaryValue& params) {
   attach_params_.reset(params.DeepCopy());
   attach_params_->GetInteger(guestview::kParameterInstanceId,
@@ -396,7 +402,14 @@ void GuestViewBase::RenderViewReady() {
 }
 
 void GuestViewBase::WebContentsDestroyed() {
+  // Let the derived class know that its WebContents is in the process of
+  // being destroyed. web_contents() is still valid at this point.
+  // TODO(fsamuel): This allows for reentrant code into WebContents during
+  // destruction. This could potentially lead to bugs. Perhaps we should get rid
+  // of this?
   GuestDestroyed();
+
+  // Self-destruct.
   delete this;
 }
 
diff --git a/extensions/browser/guest_view/guest_view_base.h b/extensions/browser/guest_view/guest_view_base.h
index f255e1f..7c3bd43 100644
--- a/extensions/browser/guest_view/guest_view_base.h
+++ b/extensions/browser/guest_view/guest_view_base.h
@@ -102,7 +102,7 @@ class GuestViewBase : public content::BrowserPluginGuestDelegate,
   virtual void GuestDestroyed() {}
 
   // This method is invoked when the guest RenderView is ready, e.g. because we
-  // recreated it after a crash.
+  // recreated it after a crash or after reattachment.
   //
   // This gives the derived class an opportunity to perform some initialization
   // work.
@@ -224,7 +224,10 @@ class GuestViewBase : public content::BrowserPluginGuestDelegate,
     return opener_.get();
   }
 
-  // Sets some additional chrome/ initialization parameters.
+  // Destroy this guest.
+  void Destroy();
+
+  // Saves the attach state of the custom element hosting this GuestView.
   void SetAttachParams(const base::DictionaryValue& params);
   void SetOpener(GuestViewBase* opener);
 
@@ -235,7 +238,6 @@ class GuestViewBase : public content::BrowserPluginGuestDelegate,
                                    int exit_code) OVERRIDE;
 
   // BrowserPluginGuestDelegate implementation.
-  virtual void Destroy() OVERRIDE FINAL;
   virtual void DidAttach(int guest_proxy_routing_id) OVERRIDE FINAL;
   virtual void ElementSizeChanged(const gfx::Size& old_size,
                                   const gfx::Size& new_size) OVERRIDE FINAL;
diff --git a/extensions/browser/guest_view/web_view/web_view_constants.cc b/extensions/browser/guest_view/web_view/web_view_constants.cc
index 9454292..9526d43 100644
--- a/extensions/browser/guest_view/web_view/web_view_constants.cc
+++ b/extensions/browser/guest_view/web_view/web_view_constants.cc
@@ -42,7 +42,6 @@ const char kEventLoadStop[] = "webViewInternal.onLoadStop";
 const char kEventMessage[] = "webViewInternal.onMessage";
 const char kEventNewWindow[] = "webViewInternal.onNewWindow";
 const char kEventPermissionRequest[] = "webViewInternal.onPermissionRequest";
-const char kEventPluginDestroyed[] = "webViewInternal.onPluginDestroyed";
 const char kEventResponsive[] = "webViewInternal.onResponsive";
 const char kEventSizeChanged[] = "webViewInternal.onSizeChanged";
 const char kEventUnresponsive[] = "webViewInternal.onUnresponsive";
diff --git a/extensions/browser/guest_view/web_view/web_view_constants.h b/extensions/browser/guest_view/web_view/web_view_constants.h
index c7ee206..d6d0b50 100644
--- a/extensions/browser/guest_view/web_view/web_view_constants.h
+++ b/extensions/browser/guest_view/web_view/web_view_constants.h
@@ -46,7 +46,6 @@ extern const char kEventLoadStop[];
 extern const char kEventMessage[];
 extern const char kEventNewWindow[];
 extern const char kEventPermissionRequest[];
-extern const char kEventPluginDestroyed[];
 extern const char kEventResponsive[];
 extern const char kEventSizeChanged[];
 extern const char kEventUnresponsive[];
diff --git a/extensions/browser/guest_view/web_view/web_view_guest.cc b/extensions/browser/guest_view/web_view/web_view_guest.cc
index 2e124e0..f00a682 100644
--- a/extensions/browser/guest_view/web_view/web_view_guest.cc
+++ b/extensions/browser/guest_view/web_view/web_view_guest.cc
@@ -287,7 +287,7 @@ void WebViewGuest::DidAttachToEmbedder() {
 
   std::string src;
   if (attach_params()->GetString(webview::kAttributeSrc, &src) && !src.empty())
-    NavigateGuest(src);
+    NavigateGuest(src, false /* force_navigation */);
 
   if (GetOpener()) {
     // We need to do a navigation here if the target URL has changed between
@@ -299,7 +299,7 @@ void WebViewGuest::DidAttachToEmbedder() {
     if (it != GetOpener()->pending_new_windows_.end()) {
       const NewWindowInfo& new_window_info = it->second;
       if (new_window_info.changed || !web_contents()->HasOpener())
-        NavigateGuest(new_window_info.url.spec());
+        NavigateGuest(new_window_info.url.spec(), false /* force_navigation */);
     } else {
       NOTREACHED();
     }
@@ -404,10 +404,6 @@ void WebViewGuest::WillDestroy() {
   if (!attached() && GetOpener())
     GetOpener()->pending_new_windows_.erase(this);
   DestroyUnattachedWindows();
-
-  scoped_ptr<base::DictionaryValue> args(new base::DictionaryValue());
-  DispatchEventToEmbedder(
-      new GuestViewBase::Event(webview::kEventPluginDestroyed, args.Pass()));
 }
 
 bool WebViewGuest::AddMessageToConsole(WebContents* source,
@@ -679,6 +675,8 @@ void WebViewGuest::DidCommitProvisionalLoadForFrame(
     content::RenderFrameHost* render_frame_host,
     const GURL& url,
     ui::PageTransition transition_type) {
+  if (!render_frame_host->GetParent())
+    src_ = url;
   scoped_ptr<base::DictionaryValue> args(new base::DictionaryValue());
   args->SetString(guestview::kUrl, url.spec());
   args->SetBoolean(guestview::kIsTopLevel, !render_frame_host->GetParent());
@@ -898,7 +896,11 @@ content::ColorChooser* WebViewGuest::OpenColorChooser(
       web_contents, color, suggestions);
 }
 
-void WebViewGuest::NavigateGuest(const std::string& src) {
+void WebViewGuest::NavigateGuest(const std::string& src,
+                                 bool force_navigation) {
+  if (src.empty())
+    return;
+
   GURL url = ResolveURL(src);
 
   // Do not allow navigating a guest to schemes other than known safe schemes.
@@ -914,6 +916,8 @@ void WebViewGuest::NavigateGuest(const std::string& src) {
               net::ErrorToShortString(net::ERR_ABORTED));
     return;
   }
+  if (!force_navigation && (src_ == url))
+    return;
 
   GURL validated_url(url);
   web_contents()->GetRenderProcessHost()->FilterURL(false, &validated_url);
diff --git a/extensions/browser/guest_view/web_view/web_view_guest.h b/extensions/browser/guest_view/web_view/web_view_guest.h
index ccf52ed..f1e1e83 100644
--- a/extensions/browser/guest_view/web_view/web_view_guest.h
+++ b/extensions/browser/guest_view/web_view/web_view_guest.h
@@ -58,7 +58,7 @@ class WebViewGuest : public GuestView<WebViewGuest>,
   static const char Type[];
 
   // Request navigating the guest to the provided |src| URL.
-  void NavigateGuest(const std::string& src);
+  void NavigateGuest(const std::string& src, bool force_navigation);
 
   // Shows the context menu for the guest.
   // |items| acts as a filter. This restricts the current context's default
@@ -343,10 +343,13 @@ class WebViewGuest : public GuestView<WebViewGuest>,
   // Stores whether the contents of the guest can be transparent.
   bool guest_opaque_;
 
+  // Stores the src URL of the WebView.
+  GURL src_;
+
   // Handles the JavaScript dialog requests.
   JavaScriptDialogHelper javascript_dialog_helper_;
 
-  // Handels permission requests.
+  // Handles permission requests.
   scoped_ptr<WebViewPermissionHelper> web_view_permission_helper_;
 
   scoped_ptr<WebViewGuestDelegate> web_view_guest_delegate_;
diff --git a/extensions/common/api/guest_view_internal.json b/extensions/common/api/guest_view_internal.json
index bafb2ed..9a96f0b 100644
--- a/extensions/common/api/guest_view_internal.json
+++ b/extensions/common/api/guest_view_internal.json
@@ -67,6 +67,16 @@
         ]
       },
       {
+        "name": "destroyGuest",
+        "type": "function",
+        "parameters": [
+          {
+            "type": "integer",
+            "name": "instanceId"
+          }
+        ]
+      },
+      {
         "name": "setAutoSize",
         "type": "function",
         "parameters": [
diff --git a/extensions/renderer/resources/web_view.js b/extensions/renderer/resources/web_view.js
index 3cf20f9..095d377 100644
--- a/extensions/renderer/resources/web_view.js
+++ b/extensions/renderer/resources/web_view.js
@@ -87,6 +87,7 @@ function WebViewInternal(webviewNode) {
   privates(webviewNode).internal = this;
   this.webviewNode = webviewNode;
   this.attached = false;
+  this.pendingGuestCreation = false;
   this.elementAttached = false;
 
   this.beforeFirstNavigation = true;
@@ -142,6 +143,7 @@ WebViewInternal.prototype.reset = function() {
   // heard back from createGuest yet. We will not reset the flag in this case so
   // that we don't end up allocating a second guest.
   if (this.guestInstanceId) {
+    GuestViewInternal.destroyGuest(this.guestInstanceId);
     this.guestInstanceId = undefined;
     this.beforeFirstNavigation = true;
     this.validPartitionId = true;
@@ -542,25 +544,18 @@ WebViewInternal.prototype.handleBrowserPluginAttributeMutation =
     this.browserPluginNode.removeAttribute('internalinstanceid');
     this.internalInstanceId = parseInt(newValue);
 
-    if (!this.deferredAttachState) {
-      this.parseAttributes();
-      return;
-    }
-
     if (!!this.guestInstanceId && this.guestInstanceId != 0) {
-      window.setTimeout(function() {
-        var isNewWindow = this.deferredAttachState ?
-            this.deferredAttachState.isNewWindow : false;
-        var params = this.buildAttachParams(isNewWindow);
-        guestViewInternalNatives.AttachGuest(
-            this.internalInstanceId,
-            this.guestInstanceId,
-            params,
-            function(w) {
-              this.contentWindow = w;
-            }.bind(this)
-        );
-      }.bind(this), 0);
+      var isNewWindow = this.deferredAttachState ?
+          this.deferredAttachState.isNewWindow : false;
+      var params = this.buildAttachParams(isNewWindow);
+      guestViewInternalNatives.AttachGuest(
+          this.internalInstanceId,
+          this.guestInstanceId,
+          params,
+          function(w) {
+            this.contentWindow = w;
+          }.bind(this)
+      );
     }
 
     return;
@@ -641,24 +636,20 @@ WebViewInternal.prototype.hasNavigated = function() {
 WebViewInternal.prototype.parseSrcAttribute = function(result) {
   if (!this.partition.validPartitionId) {
     result.error = ERROR_MSG_INVALID_PARTITION_ATTRIBUTE;
-    return false;
+    return;
   }
   this.src = this.webviewNode.getAttribute('src');
 
   if (!this.src) {
-    return true;
-  }
-
-  if (!this.elementAttached) {
-    return true;
+    return;
   }
 
   if (!this.hasGuestInstanceID()) {
     if (this.beforeFirstNavigation) {
       this.beforeFirstNavigation = false;
-      this.allocateInstanceId();
+      this.createGuest();
     }
-    return true;
+    return;
   }
 
   // Navigate to this.src.
@@ -668,17 +659,23 @@ WebViewInternal.prototype.parseSrcAttribute = function(result) {
 
 /** @return {boolean} */
 WebViewInternal.prototype.parseAttributes = function() {
+  if (!this.elementAttached) {
+    return;
+  }
   var hasNavigated = this.hasNavigated();
   var attributeValue = this.webviewNode.getAttribute('partition');
   var result = this.partition.fromAttribute(attributeValue, hasNavigated);
-  return this.parseSrcAttribute(result);
+  this.parseSrcAttribute(result);
 };
 
 WebViewInternal.prototype.hasGuestInstanceID = function() {
   return this.guestInstanceId != undefined;
 };
 
-WebViewInternal.prototype.allocateInstanceId = function() {
+WebViewInternal.prototype.createGuest = function() {
+  if (this.pendingGuestCreation) {
+    return;
+  }
   var storagePartitionId =
       this.webviewNode.getAttribute(WEB_VIEW_ATTRIBUTE_PARTITION) ||
       this.webviewNode[WEB_VIEW_ATTRIBUTE_PARTITION];
@@ -689,9 +686,15 @@ WebViewInternal.prototype.allocateInstanceId = function() {
       'webview',
       params,
       function(guestInstanceId) {
+        this.pendingGuestCreation = false;
+        if (!this.elementAttached) {
+          GuestViewInternal.destroyGuest(this.guestInstanceId);
+          return;
+        }
         this.attachWindow(guestInstanceId, false);
       }.bind(this)
   );
+  this.pendingGuestCreation = true;
 };
 
 WebViewInternal.prototype.onFrameNameChanged = function(name) {
@@ -703,10 +706,6 @@ WebViewInternal.prototype.onFrameNameChanged = function(name) {
   }
 };
 
-WebViewInternal.prototype.onPluginDestroyed = function() {
-  this.reset();
-};
-
 WebViewInternal.prototype.dispatchEvent = function(webViewEvent) {
   return this.webviewNode.dispatchEvent(webViewEvent);
 };
@@ -756,7 +755,6 @@ WebViewInternal.prototype.onAttach = function(storagePartitionId) {
   this.partition.fromAttribute(storagePartitionId, this.hasNavigated());
 };
 
-
 /** @private */
 WebViewInternal.prototype.getUserAgent = function() {
   return this.userAgentOverride || navigator.userAgent;
diff --git a/extensions/renderer/resources/web_view_events.js b/extensions/renderer/resources/web_view_events.js
index f02069b..c73a1f6 100644
--- a/extensions/renderer/resources/web_view_events.js
+++ b/extensions/renderer/resources/web_view_events.js
@@ -184,7 +184,6 @@ function WebViewEvents(webViewInternal, viewInstanceId) {
 // Sets up events.
 WebViewEvents.prototype.setup = function() {
   this.setupFrameNameChangedEvent();
-  this.setupPluginDestroyedEvent();
   this.setupWebRequestEvents();
   this.webViewInternal.setupExperimentalContextMenus();
 
@@ -200,12 +199,6 @@ WebViewEvents.prototype.setupFrameNameChangedEvent = function() {
   }.bind(this), {instanceId: this.viewInstanceId});
 };
 
-WebViewEvents.prototype.setupPluginDestroyedEvent = function() {
-  PluginDestroyedEvent.addListener(function(e) {
-    this.webViewInternal.onPluginDestroyed();
-  }.bind(this), {instanceId: this.viewInstanceId});
-};
-
 WebViewEvents.prototype.setupWebRequestEvents = function() {
   var request = {};
   var createWebRequestEvent = function(webRequestEvent) {
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 88857ba..e4053b5 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -42335,6 +42335,7 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <int value="897" label="HOTWORDPRIVATE_GETLAUNCHSTATE"/>
   <int value="898" label="HOTWORDPRIVATE_SETHOTWORDALWAYSONSEARCHENABLED"/>
   <int value="899" label="WEBVIEWINTERNAL_LOADDATAWITHBASEURL"/>
+  <int value="900" label="GUESTVIEWINTERNAL_DESTROYGUEST"/>
 </enum>
 
 <enum name="ExtensionInstallCause" type="int">