Convert OverscrollNavigationOverlayTest.ImmediateLoadOnNavigate to use the new navigation callbacks…

content/browser/web_contents/aura/overscroll_navigation_overlay_unittest.cc

 // 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.
 
 #include "content/browser/web_contents/aura/overscroll_navigation_overlay.h"
 
 #include <string.h>
 #include <utility>
 #include <vector>
 
@@ skipping 22 matching lines @@
 
 // Forces web contents to complete web page load as soon as navigation starts.
 class ImmediateLoadObserver : WebContentsObserver {
  public:
   explicit ImmediateLoadObserver(TestWebContents* contents)
       : contents_(contents) {
     Observe(contents);
   }
   ~ImmediateLoadObserver() override {}
 
+  // TODO: remove this method when PlzNavigate is turned on by default.
   void DidStartNavigationToPendingEntry(const GURL& url,
                                         ReloadType reload_type) override {
-    // Simulate immediate web page load.
-    contents_->TestSetIsLoading(false);
-    Observe(nullptr);
+    if (!IsBrowserSideNavigationEnabled()) {
+      // Simulate immediate web page load.
+      contents_->TestSetIsLoading(false);
+      Observe(nullptr);
+    }
+  }
+
+  void DidStartNavigation(NavigationHandle* navigation_handlee) override {
+    if (IsBrowserSideNavigationEnabled()) {
+      // Simulate immediate web page load.
+      contents_->TestSetIsLoading(false);
+      Observe(nullptr);
+    }
   }
 
  private:
   TestWebContents* contents_;
 
   DISALLOW_COPY_AND_ASSIGN(ImmediateLoadObserver);
 };
 
 // A subclass of TestWebContents that offers a fake content window.
 class OverscrollTestWebContents : public TestWebContents {
@@ skipping 381 matching lines @@
   EXPECT_TRUE(GetOverlay()->window_.get());
 
   // Load the page.
   contents()->CommitPendingNavigation();
   ReceivePaintUpdate();
   EXPECT_FALSE(GetOverlay()->window_.get());
   EXPECT_EQ(contents()->GetURL(), first());
 }
 
 }  // namespace content