Ignore print() during page dismissal.

chrome/browser/chrome_site_per_process_browsertest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/path_service.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 499 matching lines @@
       "var w = window.open('about:blank');\n"
       "window.domAutomationController.send(!!w);\n",
       &popup_handle_is_valid));
   popup_observer.Wait();
 
   // The popup shouldn't be blocked.
   EXPECT_TRUE(popup_handle_is_valid);
   ASSERT_EQ(2, browser()->tab_strip_model()->count());
 }
 
+IN_PROC_BROWSER_TEST_F(ChromeSitePerProcessTest, PrintOnUnloadHandler) {

[alexmos, 2017/05/23 18:01:19]

nit: the name makes it sound like we're expecting print to still work in unload.
:)  PrintIgnoredInUnloadHandler, perhaps?

[lfg, 2017/05/23 18:38:52]

Done.

+  ui_test_utils::NavigateToURL(
+      browser(), GURL(embedded_test_server()->GetURL("a.com", "/title1.html")));
+
+  content::WebContents* active_web_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+
+  // Create 2 iframes and navigate them to b.com.
+  EXPECT_TRUE(ExecuteScript(active_web_contents,
+                            "var i = document.createElement('iframe'); i.id = "
+                            "'child-0'; document.body.appendChild(i);"));
+  EXPECT_TRUE(ExecuteScript(active_web_contents,
+                            "var i = document.createElement('iframe'); i.id = "
+                            "'child-1'; document.body.appendChild(i);"));
+  EXPECT_TRUE(NavigateIframeToURL(
+      active_web_contents, "child-0",
+      GURL(embedded_test_server()->GetURL("b.com", "/title1.html"))));
+  EXPECT_TRUE(NavigateIframeToURL(
+      active_web_contents, "child-1",
+      GURL(embedded_test_server()->GetURL("b.com", "/title1.html"))));
+
+  content::RenderFrameHost* child_0 =
+      ChildFrameAt(active_web_contents->GetMainFrame(), 0);
+  content::RenderFrameHost* child_1 =
+      ChildFrameAt(active_web_contents->GetMainFrame(), 1);
+
+  // Add an unload handler that calls print() to child-0 iframe.
+  EXPECT_TRUE(ExecuteScript(
+      child_0, "document.body.onunload = function() { print(); }"));
+
+  // Transfer child-0 to a new process hosting c.com.
+  EXPECT_TRUE(NavigateIframeToURL(
+      active_web_contents, "child-0",
+      GURL(embedded_test_server()->GetURL("c.com", "/title1.html"))));
+
+  // Check that b.com's process is still alive.
+  bool renderer_alive = false;
+  EXPECT_TRUE(ExecuteScriptAndExtractBool(
+      child_1, "window.domAutomationController.send(true);", &renderer_alive));
+  EXPECT_TRUE(renderer_alive);
+}
+
 #if BUILDFLAG(ENABLE_SPELLCHECK)
 // Class to sniff incoming IPCs for spell check messages.
 class TestSpellCheckMessageFilter : public content::BrowserMessageFilter {
  public:
   explicit TestSpellCheckMessageFilter(content::RenderProcessHost* process_host)
       : content::BrowserMessageFilter(SpellCheckMsgStart),
         process_host_(process_host),
         text_received_(false),
         message_loop_runner_(base::MakeShared<content::MessageLoopRunner>()) {}
 
@@ skipping 93 matching lines @@
   scoped_refptr<TestSpellCheckMessageFilter> filter =
       browser_client.GetSpellCheckMessageFilterForProcess(
           subframe->GetProcess());
   filter->Wait();
 
   EXPECT_EQ(base::ASCIIToUTF16("zz."), filter->last_text());
 
   content::SetBrowserClientForTesting(old_browser_client);
 }
 #endif  // BUILDFLAG(ENABLE_SPELLCHECK)