Inside of content, prefer SiteInstanceImpl to SiteInstance.

content/browser/site_per_process_browsertest.cc

Index: content/browser/site_per_process_browsertest.cc
diff --git a/content/browser/site_per_process_browsertest.cc b/content/browser/site_per_process_browsertest.cc
index 17e60f38f89d59b372f8407c3671a61fbbf2e716..23e9ea246a1f63e0ecf238852334ba15bb93c9e0 100644
--- a/content/browser/site_per_process_browsertest.cc
+++ b/content/browser/site_per_process_browsertest.cc
@@ -5534,7 +5534,8 @@ IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest,
   // Instead, tell A to detach B and then send a fake proxy creation IPC to A
   // that would've come from create-child-frame code in B.  Prepare parameters
   // for that IPC ahead of the detach, while B's FrameTreeNode still exists.
-  SiteInstance* site_instance_a = root->current_frame_host()->GetSiteInstance();
+  SiteInstanceImpl* site_instance_a =
+      root->current_frame_host()->GetSiteInstance();
   RenderProcessHost* process_a =
       root->render_manager()->current_frame_host()->GetProcess();
   int new_routing_id = process_a->GetNextRoutingID();