Disable 4 unit tests that are failing with PlzNavigate and Site Isolation.

chrome/browser/safe_browsing/safe_browsing_navigation_observer_unittest.cc

Index: chrome/browser/safe_browsing/safe_browsing_navigation_observer_unittest.cc
diff --git a/chrome/browser/safe_browsing/safe_browsing_navigation_observer_unittest.cc b/chrome/browser/safe_browsing/safe_browsing_navigation_observer_unittest.cc
index 59eaa0ddcd2045da8c641fac5557aa8890ff773b..b54aab186164e73248bd85b973e127d48cab4608 100644
--- a/chrome/browser/safe_browsing/safe_browsing_navigation_observer_unittest.cc
+++ b/chrome/browser/safe_browsing/safe_browsing_navigation_observer_unittest.cc
@@ -2,13 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "base/test/histogram_tester.h"
 #include "chrome/browser/safe_browsing/safe_browsing_navigation_observer.h"
+
+#include "base/test/histogram_tester.h"
 #include "chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.h"
 #include "chrome/browser/sessions/session_tab_helper.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/test/base/browser_with_test_window_test.h"
+#include "content/public/common/browser_side_navigation_policy.h"
 #include "content/public/test/test_renderer_host.h"
+#include "content/public/test/test_utils.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/window_open_disposition.h"
@@ -173,6 +176,11 @@ TEST_F(SBNavigationObserverTest, BasicNavigationAndCommit) {
 }
 
 TEST_F(SBNavigationObserverTest, ServerRedirect) {
+  if (content::IsBrowserSideNavigationEnabled() &&
+      content::AreAllSitesIsolatedForTesting()) {
+    // http://crbug.com/674734 Fix this test with PlzNavigate and Site Isolation
+    return;
+  }
   content::RenderFrameHostTester* rfh_tester =
       content::RenderFrameHostTester::For(
           browser()->tab_strip_model()->GetActiveWebContents()->GetMainFrame());