OOPIF: Remove the FrameTreeNode when a RemoteFrame is detached.

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 f758c2f07d3e04068c5d4d9d875463397d58d71d..50cf47e2a226ea4a4b8c6af65b8540a9e291cfca 100644
--- a/content/browser/site_per_process_browsertest.cc
+++ b/content/browser/site_per_process_browsertest.cc
@@ -281,6 +281,39 @@ IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest, CrossSiteIframe) {
   EXPECT_TRUE(child->current_frame_host()->GetRenderWidgetHost());
 }
 
+// Ensure that OOPIFs are deleted after navigating to a new main frame.
+IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest, CleanupCrossSiteIframe) {

[nasko, 2015/03/30 22:58:17]

Do you think it is worthwhile having a test case that removes a subframe through
JS? It is a variation of this scenario, but seems sufficiently different to have
at test for it at some point in time.

[Charlie Reis, 2015/04/06 19:17:11]

Done.  And I'm glad you mentioned it!  By writing the test for that, I tripped
across a use case showing that my HasAncestorFrom(SiteInstance) check is
invalid.  (A frame can be detached by a process that isn't one of its parents,
if that process navigates the parent of the frame.)

+  GURL main_url(embedded_test_server()->GetURL("/site_per_process_main.html"));
+  NavigateToURL(shell(), main_url);
+
+  // It is safe to obtain the root frame tree node here, as it doesn't change.
+  FrameTreeNode* root =
+      static_cast<WebContentsImpl*>(shell()->web_contents())->
+          GetFrameTree()->root();
+
+  TestNavigationObserver observer(shell()->web_contents());
+
+  // Load cross-site page into iframe.
+  GURL url = embedded_test_server()->GetURL("foo.com", "/title2.html");
+  NavigateFrameToURL(root->child_at(0), url);
+  // Verify that the navigation succeeded and the expected URL was loaded.
+  EXPECT_TRUE(observer.last_navigation_succeeded());
+  EXPECT_EQ(url, observer.last_navigation_url());
+
+  // Ensure that we have created a new process for the subframe.
+  FrameTreeNode* child = root->child_at(0);
+  ASSERT_EQ(2U, root->child_count());
+  SiteInstance* site_instance = child->current_frame_host()->GetSiteInstance();
+  EXPECT_NE(shell()->web_contents()->GetSiteInstance(), site_instance);
+
+  // Load a new same-site page in the top-level frame.
+  GURL new_url(embedded_test_server()->GetURL("/title1.html"));
+  NavigateToURL(shell(), new_url);
+
+  // Ensure that the subframe is gone.
+  ASSERT_EQ(0U, root->child_count());
+}
+
 // Disabled for flaky crashing: crbug.com/446575
 IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest,
                        NavigateRemoteFrame) {