Move existing kSitePerProcess checks to a policy-oracle object

content/browser/frame_host/render_frame_host_manager_browsertest.cc

Index: content/browser/frame_host/render_frame_host_manager_browsertest.cc
diff --git a/content/browser/frame_host/render_frame_host_manager_browsertest.cc b/content/browser/frame_host/render_frame_host_manager_browsertest.cc
index 130790bec4097f0d29a9bdc6cfb84a9f78f56569..fe2197a92a75e1bcba7e9efa723e80f033614881 100644
--- a/content/browser/frame_host/render_frame_host_manager_browsertest.cc
+++ b/content/browser/frame_host/render_frame_host_manager_browsertest.cc
@@ -30,6 +30,7 @@
 #include "content/public/common/file_chooser_file_info.h"
 #include "content/public/common/file_chooser_params.h"
 #include "content/public/common/page_state.h"
+#include "content/public/common/site_isolation_policy.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/test/browser_test_utils.h"
 #include "content/public/test/content_browser_test.h"
@@ -341,11 +342,10 @@ IN_PROC_BROWSER_TEST_F(RenderFrameHostManagerTest,
   // Should have the same SiteInstance unless we're in site-per-process mode.
   scoped_refptr<SiteInstance> blank_site_instance(
       new_shell->web_contents()->GetSiteInstance());
-  if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kSitePerProcess))
-    EXPECT_EQ(orig_site_instance, blank_site_instance);
-  else
+  if (SiteIsolationPolicy::AreAllSitesIsolatedForTesting())
     EXPECT_NE(orig_site_instance, blank_site_instance);
+  else
+    EXPECT_EQ(orig_site_instance, blank_site_instance);
 }
 
 // Test for crbug.com/24447.  Following a cross-site link with rel=noreferrer
@@ -386,11 +386,10 @@ IN_PROC_BROWSER_TEST_F(RenderFrameHostManagerTest,
   // Should have the same SiteInstance unless we're in site-per-process mode.
   scoped_refptr<SiteInstance> noref_site_instance(
       shell()->web_contents()->GetSiteInstance());
-  if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kSitePerProcess))
-    EXPECT_EQ(orig_site_instance, noref_site_instance);
-  else
+  if (SiteIsolationPolicy::AreAllSitesIsolatedForTesting())
     EXPECT_NE(orig_site_instance, noref_site_instance);
+  else
+    EXPECT_EQ(orig_site_instance, noref_site_instance);
 }
 
 // Test for crbug.com/116192.  Targeted links should still work after the