With --site-per-process, avoid a crash when a subframe process goes away.

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 0bade5ca4a3a5fae2e6a29f6c04be86283a69b59..e536cf6adaf945c0821c7d9dc6cfa33722044d14 100644
--- a/content/browser/site_per_process_browsertest.cc
+++ b/content/browser/site_per_process_browsertest.cc
@@ -258,6 +258,68 @@ IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest, CrossSiteIframe) {
             child->current_frame_host()->GetProcess());
 }
 
+// Crash a subframe and ensures its children are cleared from the FrameTree.
+// See http://crbug.com/338508.
+// TODO(creis): Enable this on Android when we can kill the process there.
+#if defined(OS_ANDROID)
+#define MAYBE_CrashSubframe DISABLED_CrashSubframe
+#else
+#define MAYBE_CrashSubframe CrashSubframe
+#endif
+IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest, MAYBE_CrashSubframe) {
+  host_resolver()->AddRule("*", "127.0.0.1");
+  ASSERT_TRUE(test_server()->Start());
+  GURL main_url(test_server()->GetURL("files/site_per_process_main.html"));
+  NavigateToURL(shell(), main_url);
+
+  StartFrameAtDataURL();
+
+  // These must stay in scope with replace_host.
+  GURL::Replacements replace_host;
+  std::string foo_com("foo.com");
+
+  // Load cross-site page into iframe.
+  GURL cross_site_url(test_server()->GetURL("files/title2.html"));
+  replace_host.SetHostStr(foo_com);
+  cross_site_url = cross_site_url.ReplaceComponents(replace_host);
+  EXPECT_TRUE(NavigateIframeToURL(shell(), cross_site_url, "test"));
+
+  // Check the subframe process.
+  FrameTreeNode* root =
+      static_cast<WebContentsImpl*>(shell()->web_contents())->
+          GetFrameTree()->root();
+  ASSERT_EQ(1U, root->child_count());
+  FrameTreeNode* child = root->child_at(0);
+  EXPECT_NE(FrameTreeNode::kInvalidFrameId, root->frame_id());
+  EXPECT_NE(FrameTreeNode::kInvalidFrameId, root->child_at(0)->frame_id());
+
+  // Crash the subframe process.
+  RenderProcessHost* root_process = root->current_frame_host()->GetProcess();
+  RenderProcessHost* child_process = child->current_frame_host()->GetProcess();
+  {
+    RenderProcessHostWatcher crash_observer(
+        child_process,
+        RenderProcessHostWatcher::WATCH_FOR_PROCESS_EXIT);
+    base::KillProcess(child_process->GetHandle(), 0, false);
+    crash_observer.Wait();
+  }
+
+  // Ensure that the child frame still exists but has been cleared.
+  EXPECT_EQ(1U, root->child_count());
+  EXPECT_EQ(FrameTreeNode::kInvalidFrameId, root->child_at(0)->frame_id());
+
+  // Now crash the top-level page to clear the child frame.
+  {
+    RenderProcessHostWatcher crash_observer(
+        root_process,
+        RenderProcessHostWatcher::WATCH_FOR_PROCESS_EXIT);
+    base::KillProcess(root_process->GetHandle(), 0, false);
+    crash_observer.Wait();
+  }
+  EXPECT_EQ(0U, root->child_count());
+  EXPECT_EQ(FrameTreeNode::kInvalidFrameId, root->frame_id());
+}
+
 // TODO(nasko): Disable this test until out-of-process iframes is ready and the
 // security checks are back in place.
 // TODO(creis): Replace SpawnedTestServer with host_resolver to get test to run