Add tests to ensure no RFH/RVH objects leak on cross-process navigation

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 964255d6087aff23f2e20a01efd6ec2904d3fcfb..073496edb2c0c3b64f4cb0fbaa2be9260cad8962 100644
--- a/content/browser/site_per_process_browsertest.cc
+++ b/content/browser/site_per_process_browsertest.cc
@@ -459,11 +459,17 @@ IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest, CleanupCrossSiteIframe) {
   EXPECT_EQ(foo_url, observer.last_navigation_url());
 
   // Ensure that we have created a new process for the subframes.
+  RenderFrameHostImpl* child1_rfh = root->child_at(0)->current_frame_host();
+  RenderFrameHostImpl* child2_rfh = root->child_at(1)->current_frame_host();
   ASSERT_EQ(2U, root->child_count());
   EXPECT_NE(shell()->web_contents()->GetSiteInstance(),
-            root->child_at(0)->current_frame_host()->GetSiteInstance());
-  EXPECT_EQ(root->child_at(0)->current_frame_host()->GetSiteInstance(),
-            root->child_at(1)->current_frame_host()->GetSiteInstance());
+            child1_rfh->GetSiteInstance());
+  EXPECT_EQ(child1_rfh->GetSiteInstance(), child2_rfh->GetSiteInstance());
+
+  int subframe_process_id =
+      child1_rfh->GetSiteInstance()->GetProcess()->GetID();
+  int subframe_rvh_id = child1_rfh->render_view_host()->GetRoutingID();
+  EXPECT_TRUE(RenderViewHost::FromID(subframe_process_id, subframe_rvh_id));
 
   // Use Javascript in the parent to remove one of the frames and ensure that
   // the subframe goes away.
@@ -477,6 +483,9 @@ IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest, CleanupCrossSiteIframe) {
   GURL new_url(embedded_test_server()->GetURL("/title1.html"));
   NavigateToURL(shell(), new_url);
   ASSERT_EQ(0U, root->child_count());
+
+  // Ensure the RVH for the subframe gets cleaned up when the frame goes away.
+  EXPECT_FALSE(RenderViewHost::FromID(subframe_process_id, subframe_rvh_id));
 }
 
 // Ensure that root frames cannot be detached.