Add SafeBrowsing referrer chain test to illustrate "source" behaviour

This test navigates a new tab via its opener to demonstrate that the
source information in the referrer chain reflects the previously
committed URL in the navigating frame, rather than the initiator of the
navigation. This scenario is worth considering for any future attempt to
capture information about the initiator in the referrer chain.

Bug: 1096115
Change-Id: If997a84b46ea45640266cfb2e954ee291f06201f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2386755Reviewed-by: Daniel Rubery <drubery@chromium.org>
Commit-Queue: Kevin McNee <mcnee@chromium.org>
Cr-Commit-Position: refs/heads/master@{#805900}

chrome/browser/safe_browsing/safe_browsing_navigation_observer_browsertest.cc

@@ -2530,6 +2530,139 @@ IN_PROC_BROWSER_TEST_F(SBNavigationObserverBrowserTest,
   ASSERT_EQ(2, referrer_chain.size());
 }
 
+// Open a new tab to some arbitrary URL, then have the opener navigate the new
+// tab to the actual landing page where the user then clicks a link to start a
+// download.
+// TODO(drubery, mcnee): The "source" information captured in a Safe Browsing
+// |NavigationEvent| does not necessarily reflect the initiator of a navigation.
+// This test illustrates this behaviour. Note that |initial_popup_url| appears
+// to navigate itself to the landing page, even though it was navigated by its
+// opener. Investigate whether the initiator of a navigation should be reflected
+// in the referrer chain.
+IN_PROC_BROWSER_TEST_F(SBNavigationObserverBrowserTest,
+                       NewTabClientRedirectByOpener) {
+  GURL initial_url = embedded_test_server()->GetURL(kSingleFrameTestURL);
+  GURL initial_popup_url = embedded_test_server()->GetURL("/title1.html");
+  GURL landing_url = embedded_test_server()->GetURL(kLandingURL);
+  GURL download_url = embedded_test_server()->GetURL(kDownloadItemURL);
+  ui_test_utils::NavigateToURL(browser(), initial_url);
+
+  content::WebContents* opener_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+
+  ui_test_utils::TabAddedWaiter tab_added(browser());
+  content::TestNavigationObserver new_tab_nav(initial_popup_url);
+  new_tab_nav.StartWatchingNewWebContents();
+  SimulateUserGesture();
+  ASSERT_TRUE(content::ExecJs(
+      opener_contents, content::JsReplace("window.newWindow = window.open($1);",
+                                          initial_popup_url)));
+  new_tab_nav.Wait();
+  tab_added.Wait();
+
+  content::TestNavigationObserver landing_nav_observer(landing_url);
+  landing_nav_observer.WatchExistingWebContents();
+  ASSERT_TRUE(content::ExecJs(
+      opener_contents,
+      content::JsReplace("window.newWindow.location = $1;", landing_url)));
+  landing_nav_observer.Wait();
+
+  ClickTestLink("download_on_landing_page", 1, landing_url);
+
+  std::string test_server_ip(embedded_test_server()->host_port_pair().host());
+  auto* nav_list = navigation_event_list();
+  ASSERT_TRUE(nav_list);
+  ASSERT_EQ(5U, nav_list->Size());
+  VerifyNavigationEvent(GURL(),       // source_url
+                        GURL(),       // source_main_frame_url
+                        initial_url,  // original_request_url
+                        initial_url,  // destination_url
+                        true,         // is_user_initiated,
+                        true,         // has_committed
+                        false,        // has_server_redirect
+                        nav_list->Get(0));
+  VerifyNavigationEvent(initial_url,        // source_url
+                        initial_url,        // source_main_frame_url
+                        initial_popup_url,  // original_request_url
+                        initial_popup_url,  // destination_url
+                        true,               // is_user_initiated,
+                        false,              // has_committed
+                        false,              // has_server_redirect
+                        nav_list->Get(1));
+  VerifyNavigationEvent(GURL(),             // source_url
+                        GURL(),             // source_main_frame_url
+                        initial_popup_url,  // original_request_url
+                        initial_popup_url,  // destination_url
+                        false,              // is_user_initiated,
+                        true,               // has_committed
+                        false,              // has_server_redirect
+                        nav_list->Get(2));
+  VerifyNavigationEvent(initial_popup_url,  // source_url
+                        initial_popup_url,  // source_main_frame_url
+                        landing_url,        // original_request_url
+                        landing_url,        // destination_url
+                        false,              // is_user_initiated,
+                        true,               // has_committed
+                        false,              // has_server_redirect
+                        nav_list->Get(3));
+  VerifyNavigationEvent(landing_url,   // source_url
+                        landing_url,   // source_main_frame_url
+                        download_url,  // original_request_url
+                        download_url,  // destination_url
+                        true,          // is_user_initiated,
+                        false,         // has_committed
+                        false,         // has_server_redirect
+                        nav_list->Get(4));
+  VerifyHostToIpMap();
+
+  ReferrerChain referrer_chain;
+  IdentifyReferrerChainForDownload(GetDownload(), &referrer_chain);
+  EXPECT_EQ(4, referrer_chain.size());
+  VerifyReferrerChainEntry(
+      download_url,                   // url
+      GURL(),                         // main_frame_url
+      ReferrerChainEntry::EVENT_URL,  // type
+      test_server_ip,                 // ip_address
+      landing_url,                    // referrer_url
+      GURL(),                         // referrer_main_frame_url
+      false,                          // is_retargeting
+      std::vector<GURL>(),            // server redirects
+      ReferrerChainEntry::RENDERER_INITIATED_WITH_USER_GESTURE,
+      referrer_chain.Get(0));
+  VerifyReferrerChainEntry(
+      landing_url,                       // url
+      GURL(),                            // main_frame_url
+      ReferrerChainEntry::LANDING_PAGE,  // type
+      test_server_ip,                    // ip_address
+      initial_popup_url,                 // referrer_url
+      GURL(),                            // referrer_main_frame_url
+      false,                             // is_retargeting
+      std::vector<GURL>(),               // server redirects
+      ReferrerChainEntry::RENDERER_INITIATED_WITHOUT_USER_GESTURE,
+      referrer_chain.Get(1));
+  VerifyReferrerChainEntry(
+      initial_popup_url,                    // url
+      GURL(),                               // main_frame_url
+      ReferrerChainEntry::CLIENT_REDIRECT,  // type
+      test_server_ip,                       // ip_address
+      initial_url,                          // referrer_url
+      GURL(),                               // referrer_main_frame_url
+      true,                                 // is_retargeting
+      std::vector<GURL>(),                  // server redirects
+      ReferrerChainEntry::RENDERER_INITIATED_WITH_USER_GESTURE,
+      referrer_chain.Get(2));
+  VerifyReferrerChainEntry(initial_url,  // url
+                           GURL(),       // main_frame_url
+                           ReferrerChainEntry::LANDING_REFERRER,  // type
+                           test_server_ip,                        // ip_address
+                           GURL(),               // referrer_url
+                           GURL(),               // referrer_main_frame_url
+                           false,                // is_retargeting
+                           std::vector<GURL>(),  // server redirects
+                           ReferrerChainEntry::BROWSER_INITIATED,
+                           referrer_chain.Get(3));
+}
+
 class SBNavigationObserverPortalBrowserTest
     : public SBNavigationObserverBrowserTest {
  public: