PlzNavigate: Speculatively spawns a renderer process for navigations.

content/browser/frame_host/navigator_impl_unittest.cc

Index: content/browser/frame_host/navigator_impl_unittest.cc
diff --git a/content/browser/frame_host/navigator_impl_unittest.cc b/content/browser/frame_host/navigator_impl_unittest.cc
index 2258b258559dae276adc48b300c29e3e03836a22..39fad350f0945867a9686fffd954b7614e676f3a 100644
--- a/content/browser/frame_host/navigator_impl_unittest.cc
+++ b/content/browser/frame_host/navigator_impl_unittest.cc
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/command_line.h"
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "content/browser/frame_host/navigation_controller_impl.h"
@@ -15,6 +16,7 @@
 #include "content/browser/streams/stream.h"
 #include "content/common/navigation_params.h"
 #include "content/public/browser/stream_handle.h"
+#include "content/public/common/content_switches.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/common/url_utils.h"
 #include "content/test/browser_side_navigation_test_utils.h"
@@ -73,8 +75,36 @@ class NavigatorTestWithBrowserSideNavigation
     return static_cast<NavigatorImpl*>(frame_tree_node->navigator())
         ->GetNavigationRequestForNodeForTesting(frame_tree_node);
   }
+
+  TestRenderFrameHost* GetSpeculativeRenderFrameHost(
+      RenderFrameHostManager* rfhm) {
+    return static_cast<TestRenderFrameHost*>(
+        rfhm->speculative_render_frame_host_.get());
+  }
+
+  void LoadURLAndBeginNavigationOnMainFrame(const GURL& url) {
+    contents()->GetController().LoadURL(
+        url, Referrer(), ui::PAGE_TRANSITION_LINK, std::string());
+    main_test_rfh()->SendBeginNavigationWithURL(url);
+  }
 };
 
+// PlzNavigate: Test final state after a complete navigation (to avoid repeating
+// these checks).
+TEST_F(NavigatorTestWithBrowserSideNavigation, NavigationFinishedState) {
+  const GURL kUrl("http://chromium.org/");
+  contents()->NavigateAndCommit(kUrl);
+  ASSERT_TRUE(main_test_rfh());
+  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, main_test_rfh()->rfh_state());
+  EXPECT_EQ(SiteInstanceImpl::GetSiteForURL(browser_context(), kUrl),
+            main_test_rfh()->GetSiteInstance()->GetSiteURL());
+  // After a navigation is finished no speculative RenderFrameHost should
+  // exist.
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());

[nasko, 2014/12/20 00:09:09]

I'd rather not add more code to contents(), as people need to start thinking in
terms of frames. If you want to gain readability of the test code, use a static
method as in the previous patchset.

[carlosk, 2014/12/29 16:40:16]

I complied with what nasko@ and clamy@ asked for by:
- Reverting to using a local static method for getting the speculative RFH in
this test
- Leaving the supporting changes to TestWebContents as they will be needed to
make other tests work when PlzNavigate is enabled

+  // With PlzNavigate enabled a pending RenderFrameHost should never exist.
+  EXPECT_FALSE(contents()->GetPendingMainFrame());
+}
+
 // PlzNavigate: Test that a proper NavigationRequest is created by
 // BeginNavigation.
 // Note that all PlzNavigate methods on the browser side require the use of the
@@ -85,9 +115,10 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, BeginNavigation) {
   const GURL kUrl3("http://www.gmail.com/");
 
   contents()->NavigateAndCommit(kUrl1);
+  FrameTreeNode* root = contents()->GetFrameTree()->root();
+  RenderFrameHostManager* root_rfhm = root->render_manager();
 
   // Add a subframe.
-  FrameTreeNode* root = contents()->GetFrameTree()->root();
   TestRenderFrameHost* subframe_rfh = static_cast<TestRenderFrameHost*>(
       contents()->GetFrameTree()->AddFrame(
           root, root->current_frame_host()->GetProcess()->GetID(), 14,
@@ -95,6 +126,9 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, BeginNavigation) {
   EXPECT_TRUE(subframe_rfh);
 
   FrameTreeNode* subframe_node = subframe_rfh->frame_tree_node();
+  RenderFrameHostManager* subframe_rfhm = subframe_node->render_manager();
+  EXPECT_NE(root_rfhm, subframe_rfhm);
+
   SendRequestNavigation(subframe_rfh->frame_tree_node(), kUrl2);
   // There is no previous renderer in the subframe, so BeginNavigation is
   // handled already.
@@ -109,10 +143,20 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, BeginNavigation) {
   EXPECT_EQ(kUrl1, subframe_loader->request_info()->first_party_for_cookies);
   EXPECT_FALSE(subframe_loader->request_info()->is_main_frame);
   EXPECT_TRUE(subframe_loader->request_info()->parent_is_main_frame);
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(root_rfhm));
+
+  // Subframe navigations should not create a speculative RenderFrameHost.
+  // (unless site-per-process is enabled).
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kSitePerProcess)) {
+    EXPECT_TRUE(GetSpeculativeRenderFrameHost(subframe_rfhm));
+  } else {
+    EXPECT_FALSE(GetSpeculativeRenderFrameHost(subframe_rfhm));
+  }
 
   SendRequestNavigation(root, kUrl3);
   // Simulate a BeginNavigation IPC on the main frame.
-  contents()->GetMainFrame()->SendBeginNavigationWithURL(kUrl3);
+  main_test_rfh()->SendBeginNavigationWithURL(kUrl3);
   NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(root);
   TestNavigationURLLoader* main_loader =
       GetLoaderForNavigationRequest(main_request);
@@ -122,6 +166,16 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, BeginNavigation) {
   EXPECT_EQ(kUrl3, main_loader->request_info()->first_party_for_cookies);
   EXPECT_TRUE(main_loader->request_info()->is_main_frame);
   EXPECT_FALSE(main_loader->request_info()->parent_is_main_frame);
+
+  // Main frame navigations to different sites should use a speculative
+  // RenderFrameHost.
+  EXPECT_TRUE(GetSpeculativeRenderFrameHost(root_rfhm));
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kSitePerProcess)) {
+    EXPECT_TRUE(GetSpeculativeRenderFrameHost(subframe_rfhm));
+  } else {
+    EXPECT_FALSE(GetSpeculativeRenderFrameHost(subframe_rfhm));
+  }
 }
 
 // PlzNavigate: Test that RequestNavigation creates a NavigationRequest and that
@@ -130,12 +184,17 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoLiveRenderer) {
   const GURL kUrl("http://www.google.com/");
 
   EXPECT_FALSE(main_test_rfh()->render_view_host()->IsRenderViewLive());
-  FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+  RenderFrameHostImpl* rfh = main_test_rfh();
+  FrameTreeNode* node = rfh->frame_tree_node();
   SendRequestNavigation(node, kUrl);
-  NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
+
   // A NavigationRequest should have been generated.
+  NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
   EXPECT_TRUE(main_request != NULL);
-  RenderFrameHostImpl* rfh = main_test_rfh();
+
+  // As we're re-using the current RenderFrameHost, no speculative one should be
+  // created.
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
 
   // Now return the response without any redirects. This will cause the
   // navigation to commit at the same URL.
@@ -151,24 +210,24 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoLiveRenderer) {
   EXPECT_TRUE(main_test_rfh()->render_view_host()->IsRenderViewLive());
 }
 
-// PlzNavigate: Test that commiting an HTTP 204 or HTTP 205 response cancels the
-// navigation.
+// PlzNavigate: Test that committing an HTTP 204 or HTTP 205 response cancels
+// the navigation.
 TEST_F(NavigatorTestWithBrowserSideNavigation, NoContent) {
   const GURL kUrl1("http://www.chromium.org/");
   const GURL kUrl2("http://www.google.com/");
 
   // Load a URL.
   contents()->NavigateAndCommit(kUrl1);
-  RenderFrameHostImpl* rfh = main_test_rfh();
-  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, rfh->rfh_state());
   FrameTreeNode* node = main_test_rfh()->frame_tree_node();
 
   // Navigate to a different site.
-  SendRequestNavigation(node, kUrl2);
-  main_test_rfh()->SendBeginNavigationWithURL(kUrl2);
+  LoadURLAndBeginNavigationOnMainFrame(kUrl2);

[clamy, 2014/12/19 13:35:57]

Considering that the unit tests are for NavigatorImpl and the navigation logic
specifically, I'm not terribly fan of abstracting it away in this helper
function. I don't know what the other reviewers think about it though.

[nasko, 2014/12/20 00:09:09]

I'd second that, mainly since the abstraction is just two very simple method
calls.

[carlosk, 2014/12/29 16:40:16]

They were 2 repetitive calls that apart from the URL contained a lot of default
valued parameters. It looked cleaner to me and the implementation was close by.

But I didn't feel strongly about it and it's now reverted.

   NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request);
 
+  // Navigations to a different site do create a speculative RenderFrameHost.
+  EXPECT_TRUE(contents()->GetSpeculativeMainFrame());
+
   // Commit an HTTP 204 response.
   scoped_refptr<ResourceResponse> response(new ResourceResponse);
   const char kNoContentHeaders[] = "HTTP/1.1 204 No Content\0\0";
@@ -177,17 +236,19 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoContent) {
   GetLoaderForNavigationRequest(main_request)->CallOnResponseStarted(
       response, MakeEmptyStream());
 
-  // There should be no pending RenderFrameHost; the navigation was aborted.
+  // There should be no pending nor speculative RenderFrameHost; the navigation
+  // was aborted.
   EXPECT_FALSE(GetNavigationRequestForFrameTreeNode(node));
-  EXPECT_FALSE(node->render_manager()->pending_frame_host());
+  EXPECT_FALSE(contents()->GetPendingMainFrame());
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
 
   // Now, repeat the test with 205 Reset Content.
 
   // Navigate to a different site again.
-  SendRequestNavigation(node, kUrl2);
-  main_test_rfh()->SendBeginNavigationWithURL(kUrl2);
+  LoadURLAndBeginNavigationOnMainFrame(kUrl2);
   main_request = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request);
+  EXPECT_TRUE(contents()->GetSpeculativeMainFrame());
 
   // Commit an HTTP 205 response.
   response = new ResourceResponse;
@@ -197,9 +258,11 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoContent) {
   GetLoaderForNavigationRequest(main_request)->CallOnResponseStarted(
       response, MakeEmptyStream());
 
-  // There should be no pending RenderFrameHost; the navigation was aborted.
+  // There should be no pending nor speculative RenderFrameHost; the navigation
+  // was aborted.
   EXPECT_FALSE(GetNavigationRequestForFrameTreeNode(node));
-  EXPECT_FALSE(node->render_manager()->pending_frame_host());
+  EXPECT_FALSE(contents()->GetPendingMainFrame());
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
 }
 
 // PlzNavigate: Test that a new RenderFrameHost is created when doing a cross
@@ -210,41 +273,43 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, CrossSiteNavigation) {
 
   contents()->NavigateAndCommit(kUrl1);
   RenderFrameHostImpl* rfh = main_test_rfh();
-  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, rfh->rfh_state());
   FrameTreeNode* node = main_test_rfh()->frame_tree_node();
 
   // Navigate to a different site.
-  SendRequestNavigation(node, kUrl2);
-  main_test_rfh()->SendBeginNavigationWithURL(kUrl2);
+  LoadURLAndBeginNavigationOnMainFrame(kUrl2);
   NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request);
+  EXPECT_TRUE(contents()->GetSpeculativeMainFrame());
 
   scoped_refptr<ResourceResponse> response(new ResourceResponse);
   GetLoaderForNavigationRequest(main_request)->CallOnResponseStarted(
       response, MakeEmptyStream());
-  RenderFrameHostImpl* pending_rfh =
-      node->render_manager()->pending_frame_host();
-  ASSERT_TRUE(pending_rfh);
-  EXPECT_NE(pending_rfh, rfh);
-  EXPECT_TRUE(pending_rfh->IsRenderFrameLive());
-  EXPECT_TRUE(pending_rfh->render_view_host()->IsRenderViewLive());
+  EXPECT_TRUE(contents()->GetSpeculativeMainFrame());
+
+  contents()->CommitPendingNavigation();
+  RenderFrameHostImpl* final_rfh = main_test_rfh();
+  ASSERT_TRUE(final_rfh);
+  EXPECT_NE(rfh, final_rfh);
+  EXPECT_TRUE(final_rfh->IsRenderFrameLive());
+  EXPECT_TRUE(final_rfh->render_view_host()->IsRenderViewLive());
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
 }
 
-// PlzNavigate: Test that redirects are followed.
+// PlzNavigate: Test that redirects are followed and the speculative renderer
+// logic behaves as expected.
 TEST_F(NavigatorTestWithBrowserSideNavigation, RedirectCrossSite) {
   const GURL kUrl1("http://www.chromium.org/");
   const GURL kUrl2("http://www.google.com/");
 
   contents()->NavigateAndCommit(kUrl1);
   RenderFrameHostImpl* rfh = main_test_rfh();
-  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, rfh->rfh_state());
   FrameTreeNode* node = main_test_rfh()->frame_tree_node();
 
   // Navigate to a URL on the same site.
-  SendRequestNavigation(node, kUrl1);
-  main_test_rfh()->SendBeginNavigationWithURL(kUrl1);
+  LoadURLAndBeginNavigationOnMainFrame(kUrl1);
   NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request);
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
 
   // It then redirects to another site.
   net::RedirectInfo redirect_info;
@@ -252,52 +317,65 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, RedirectCrossSite) {
   redirect_info.new_method = "GET";
   redirect_info.new_url = kUrl2;
   redirect_info.new_first_party_for_cookies = kUrl2;
- scoped_refptr<ResourceResponse> response(new ResourceResponse);
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
   GetLoaderForNavigationRequest(main_request)->CallOnRequestRedirected(
       redirect_info, response);
 
   // The redirect should have been followed.
   EXPECT_EQ(1, GetLoaderForNavigationRequest(main_request)->redirect_count());
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
 
   // Then it commits.
   response = new ResourceResponse;
   GetLoaderForNavigationRequest(main_request)->CallOnResponseStarted(
       response, MakeEmptyStream());
-  RenderFrameHostImpl* pending_rfh =
-      node->render_manager()->pending_frame_host();
-  ASSERT_TRUE(pending_rfh);
-  EXPECT_NE(pending_rfh, rfh);
-  EXPECT_TRUE(pending_rfh->IsRenderFrameLive());
-  EXPECT_TRUE(pending_rfh->render_view_host()->IsRenderViewLive());
+  RenderFrameHost* last_speculative_rfh = contents()->GetSpeculativeMainFrame();
+  EXPECT_TRUE(last_speculative_rfh);
+
+  // And commits provisional load.
+  contents()->CommitPendingNavigation();
+  RenderFrameHostImpl* final_rfh = main_test_rfh();
+  ASSERT_TRUE(final_rfh);
+  EXPECT_NE(rfh, final_rfh);
+  EXPECT_EQ(last_speculative_rfh, final_rfh);
+  EXPECT_TRUE(final_rfh->IsRenderFrameLive());
+  EXPECT_TRUE(final_rfh->render_view_host()->IsRenderViewLive());
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
 }
 
-// PlzNavigate: Test that a navigation is cancelled if another request has been
-// issued in the meantime.
+// PlzNavigate: Test that a navigation is canceled if another request has been
+// issued in the meantime. Also confirms that the speculative renderer is
+// correctly updated in the process.
 TEST_F(NavigatorTestWithBrowserSideNavigation, ReplacePendingNavigation) {
   const GURL kUrl0("http://www.wikipedia.org/");
-  const GURL kUrl0_site = SiteInstance::GetSiteForURL(browser_context(), kUrl0);
   const GURL kUrl1("http://www.chromium.org/");
+  const GURL kUrl1_site = SiteInstance::GetSiteForURL(browser_context(), kUrl1);
   const GURL kUrl2("http://www.google.com/");
   const GURL kUrl2_site = SiteInstance::GetSiteForURL(browser_context(), kUrl2);
 
   // Initialization.
   contents()->NavigateAndCommit(kUrl0);
   FrameTreeNode* node = main_test_rfh()->frame_tree_node();
-  EXPECT_EQ(kUrl0_site, main_test_rfh()->GetSiteInstance()->GetSiteURL());
 
   // Request navigation to the 1st URL.
-  SendRequestNavigation(node, kUrl1);
-  main_test_rfh()->SendBeginNavigationWithURL(kUrl1);
+  LoadURLAndBeginNavigationOnMainFrame(kUrl1);
   NavigationRequest* request1 = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(request1);
   EXPECT_EQ(kUrl1, request1->common_params().url);
   base::WeakPtr<TestNavigationURLLoader> loader1 =
       GetLoaderForNavigationRequest(request1)->AsWeakPtr();
 
+  // Confirm a speculative RFH was created.
+  ASSERT_TRUE(contents()->GetSpeculativeMainFrame());
+  int32 site_instance_id_1 =
+      contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetId();
+  EXPECT_EQ(
+      kUrl1_site,
+      contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetSiteURL());
+
   // Request navigation to the 2nd URL; the NavigationRequest must have been
   // replaced by a new one with a different URL.
-  SendRequestNavigation(node, kUrl2);
-  main_test_rfh()->SendBeginNavigationWithURL(kUrl2);
+  LoadURLAndBeginNavigationOnMainFrame(kUrl2);
   NavigationRequest* request2 = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(request2);
   EXPECT_EQ(kUrl2, request2->common_params().url);
@@ -305,18 +383,31 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, ReplacePendingNavigation) {
   // Confirm that the first loader got destroyed.
   EXPECT_FALSE(loader1);
 
-  // Confirm that the commit corresponds to the new request.
+  // Confirm that a new speculative RFH was created.
+  ASSERT_TRUE(contents()->GetSpeculativeMainFrame());
+  int32 site_instance_id_2 =
+      contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetId();
+  EXPECT_NE(site_instance_id_1, site_instance_id_2);
+
+  // Commit.
   scoped_refptr<ResourceResponse> response(new ResourceResponse);
   GetLoaderForNavigationRequest(request2)->CallOnResponseStarted(
       response, MakeEmptyStream());
-  RenderFrameHostImpl* pending_rfh =
-      node->render_manager()->pending_frame_host();
-  ASSERT_TRUE(pending_rfh);
-  EXPECT_EQ(kUrl2_site, pending_rfh->GetSiteInstance()->GetSiteURL());
+
+  // And commit provisional load.
+  contents()->CommitPendingNavigation();
+
+  // Confirm that the commit corresponds to the new request.
+  ASSERT_TRUE(main_test_rfh());
+  EXPECT_EQ(kUrl2_site, main_test_rfh()->GetSiteInstance()->GetSiteURL());
+
+  // Confirm that the committed RFH is the new speculative one.
+  EXPECT_EQ(site_instance_id_2, main_test_rfh()->GetSiteInstance()->GetId());
 }
 
 // PlzNavigate: Test that a reload navigation is properly signaled to the
-// renderer when the navigation can commit.
+// renderer when the navigation can commit. Speculative renderers should not be
+// created at any step.
 TEST_F(NavigatorTestWithBrowserSideNavigation, Reload) {
   const GURL kUrl("http://www.google.com/");
   contents()->NavigateAndCommit(kUrl);
@@ -325,27 +416,179 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, Reload) {
   SendRequestNavigationWithParameters(
       node, kUrl, Referrer(), ui::PAGE_TRANSITION_LINK,
       NavigationController::RELOAD);
-  contents()->GetMainFrame()->SendBeginNavigationWithURL(kUrl);
+  main_test_rfh()->SendBeginNavigationWithURL(kUrl);
   // A NavigationRequest should have been generated.
   NavigationRequest* main_request =
       GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request != NULL);
   EXPECT_EQ(FrameMsg_Navigate_Type::RELOAD,
             main_request->common_params().navigation_type);
-  int page_id = contents()->GetMaxPageIDForSiteInstance(
-                    main_test_rfh()->GetSiteInstance()) + 1;
-  main_test_rfh()->SendNavigate(page_id, kUrl);
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
+
+  main_test_rfh()->SendNavigate(10, kUrl);

[clamy, 2014/12/19 13:35:57]

Why 10?

[carlosk, 2014/12/29 16:40:16]

I was just setting a value high enough. I fixed them to reflect the number of
navigations inside the same site instance (that seems to be what they
represent).

+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
 
   // Now do a shift+reload.
   SendRequestNavigationWithParameters(
       node, kUrl, Referrer(), ui::PAGE_TRANSITION_LINK,
       NavigationController::RELOAD_IGNORING_CACHE);
-  contents()->GetMainFrame()->SendBeginNavigationWithURL(kUrl);
+  main_test_rfh()->SendBeginNavigationWithURL(kUrl);
   // A NavigationRequest should have been generated.
   main_request = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request != NULL);
   EXPECT_EQ(FrameMsg_Navigate_Type::RELOAD_IGNORING_CACHE,
             main_request->common_params().navigation_type);
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
+}
+
+// PlzNavigate: Confirm that a speculative RenderFrameHost is used when
+// navigating from one site to the another.
+TEST_F(NavigatorTestWithBrowserSideNavigation,
+       SpeculativeRendererWorksBaseCase) {
+  // Navigate to an initial site.
+  const GURL kUrlInit("http://wikipedia.org/");
+  contents()->NavigateAndCommit(kUrlInit);
+  FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+
+  // Begin navigating to another site.
+  const GURL kUrl("http://google.com/");
+  LoadURLAndBeginNavigationOnMainFrame(kUrl);
+  ASSERT_TRUE(contents()->GetSpeculativeMainFrame());
+  EXPECT_NE(contents()->GetSpeculativeMainFrame(), main_test_rfh());
+  EXPECT_EQ(
+      SiteInstanceImpl::GetSiteForURL(browser_context(), kUrl),
+      contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetSiteURL());
+  EXPECT_FALSE(contents()->GetPendingMainFrame());
+  int32 site_instance_id =
+      contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetId();
+
+  // Ask Navigator to commit the navigation by simulating a call to
+  // OnResponseStarted.
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
+  GetLoaderForNavigationRequest(GetNavigationRequestForFrameTreeNode(node))
+      ->CallOnResponseStarted(response, MakeEmptyStream());
+  ASSERT_TRUE(contents()->GetSpeculativeMainFrame());
+  EXPECT_EQ(site_instance_id,
+            contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetId());
+  EXPECT_FALSE(contents()->GetPendingMainFrame());
+
+  // Invoke OnDidCommitProvisionalLoad.
+  contents()->CommitPendingNavigation();
+  EXPECT_EQ(site_instance_id, main_test_rfh()->GetSiteInstance()->GetId());
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
+  EXPECT_FALSE(contents()->GetPendingMainFrame());
+}
+
+// PlzNavigate: Confirm that a speculative RenderFrameHost is thrown away when
+// the final URL's site differs from the initial one due to redirects.
+TEST_F(NavigatorTestWithBrowserSideNavigation,
+       SpeculativeRendererDiscardedAfterRedirectToAnotherSite) {
+  // Navigate to an initial site.
+  const GURL kUrlInit("http://wikipedia.org/");
+  contents()->NavigateAndCommit(kUrlInit);
+  FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+  int32 init_site_instance_id = main_test_rfh()->GetSiteInstance()->GetId();
+
+  // Begin navigating to another site.
+  const GURL kUrl("http://google.com/");
+  LoadURLAndBeginNavigationOnMainFrame(kUrl);
+  int32 site_instance_id =
+      contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetId();
+  EXPECT_EQ(init_site_instance_id, main_test_rfh()->GetSiteInstance()->GetId());
+  ASSERT_TRUE(contents()->GetSpeculativeMainFrame());
+  EXPECT_NE(contents()->GetSpeculativeMainFrame(), main_test_rfh());
+  EXPECT_EQ(
+      SiteInstanceImpl::GetSiteForURL(browser_context(), kUrl),
+      contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetSiteURL());
+
+  // It then redirects to yet another site.
+  NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
+  ASSERT_TRUE(main_request);
+  const GURL kUrlRedirect("https://www.google.com/");
+  net::RedirectInfo redirect_info;
+  redirect_info.status_code = 302;
+  redirect_info.new_method = "GET";
+  redirect_info.new_url = kUrlRedirect;
+  redirect_info.new_first_party_for_cookies = kUrlRedirect;
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
+  GetLoaderForNavigationRequest(main_request)
+      ->CallOnRequestRedirected(redirect_info, response);
+  EXPECT_EQ(init_site_instance_id, main_test_rfh()->GetSiteInstance()->GetId());
+  ASSERT_TRUE(contents()->GetSpeculativeMainFrame());
+
+  // TODO(carlosk): once the speculative RenderFrameHost updates with redirects
+  // this next check will be changed to verify that it actually happens.
+  EXPECT_EQ(site_instance_id,
+            contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetId());
+
+  // Commit the navigation with Navigator by simulating the call to
+  // OnResponseStarted.
+  response = new ResourceResponse;
+  GetLoaderForNavigationRequest(main_request)
+      ->CallOnResponseStarted(response, MakeEmptyStream());
+  EXPECT_EQ(init_site_instance_id, main_test_rfh()->GetSiteInstance()->GetId());
+
+  // Once commit happens the speculative RenderFrameHost is already updated to
+  // match the known final SiteInstance.
+  ASSERT_TRUE(contents()->GetSpeculativeMainFrame());
+  EXPECT_EQ(
+      SiteInstanceImpl::GetSiteForURL(browser_context(), kUrlRedirect),
+      contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetSiteURL());
+  int32 redirect_site_instance_id =
+      contents()->GetSpeculativeMainFrame()->GetSiteInstance()->GetId();
+
+  // Invoke OnDidCommitProvisionalLoad.
+  contents()->CommitPendingNavigation();
+
+  // And finally on commit-provisional-load the already created RenderFrameHost
+  // is made active.
+  EXPECT_EQ(redirect_site_instance_id,
+            main_test_rfh()->GetSiteInstance()->GetId());
+  EXPECT_FALSE(contents()->GetSpeculativeMainFrame());
+}
+
+// PlzNavigate: Verify that a previously swapped-out RenderFrameHost is
+// correctly reused when spawning a speculative RenderFrameHost in a navigation
+// using the same SiteInstance.
+TEST_F(NavigatorTestWithBrowserSideNavigation,
+       SpeculativeRendererReuseSwappedOutRFH) {
+  // Navigate to an initial site.
+  const GURL kUrl1("http://wikipedia.org/");
+  contents()->NavigateAndCommit(kUrl1);
+  RenderFrameHostImpl* rfh1 = main_test_rfh();
+  FrameTreeNode* node = rfh1->frame_tree_node();
+  RenderFrameHostManager* rfhm = node->render_manager();
+
+  // Increment active frame count to cause the RenderFrameHost to be swapped out
+  // (instead of immediately destroyed).
+  rfh1->GetSiteInstance()->increment_active_frame_count();
+
+  // Navigate to another site to swap-out the initial RenderFrameHost.
+  const GURL kUrl2("http://chromium.org/");
+  contents()->NavigateAndCommit(kUrl2);
+  ASSERT_NE(rfh1, main_test_rfh());
+  EXPECT_NE(RenderFrameHostImpl::STATE_DEFAULT, rfh1->rfh_state());
+  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, main_test_rfh()->rfh_state());
+  EXPECT_TRUE(rfhm->IsOnSwappedOutList(rfh1));
+
+  // Now go back to the initial site so the swapped-out RenderFrameHost should
+  // be reused.
+  LoadURLAndBeginNavigationOnMainFrame(kUrl1);
+  EXPECT_EQ(rfh1, contents()->GetSpeculativeMainFrame());
+  EXPECT_NE(RenderFrameHostImpl::STATE_DEFAULT,
+            contents()->GetSpeculativeMainFrame()->rfh_state());
+
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
+  GetLoaderForNavigationRequest(GetNavigationRequestForFrameTreeNode(node))
+      ->CallOnResponseStarted(response, MakeEmptyStream());
+  EXPECT_EQ(rfh1, contents()->GetSpeculativeMainFrame());
+  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT,
+            contents()->GetSpeculativeMainFrame()->rfh_state());
+
+  contents()->CommitPendingNavigation();
+  EXPECT_EQ(rfh1, main_test_rfh());
+  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, rfh1->rfh_state());
+  EXPECT_FALSE(rfhm->IsOnSwappedOutList(rfh1));
 }
 
 }  // namespace content