Drop queued IPC messages if the child process dies while spawning

content/browser/child_process_launcher_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 "content/browser/child_process_launcher.h"
+#include "content/browser/renderer_host/render_process_host_impl.h"
+#include "content/public/browser/navigation_entry.h"
+#include "content/public/browser/web_contents.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/test/content_browser_test.h"
 #include "content/public/test/content_browser_test_utils.h"
+#include "content/public/test/test_navigation_observer.h"
+#include "content/shell/browser/shell.h"
+
+namespace {
+
+class MockChildProcessLauncherClient
+    : public content::ChildProcessLauncher::Client {
+ public:
+  MockChildProcessLauncherClient()
+      : client_(nullptr), simulate_failure_(false) {}
+
+  void OnProcessLaunched() override {
+    if (simulate_failure_)
+      client_->OnProcessLaunchFailed();
+    else
+      client_->OnProcessLaunched();
+  };
+  void OnProcessLaunchFailed() override { client_->OnProcessLaunchFailed(); };
+
+  content::ChildProcessLauncher::Client* client_;
+  bool simulate_failure_;
+};
+
+}
 
 namespace content {
 
-typedef ContentBrowserTest ChildProcessLauncherBrowserTest;
+class ChildProcessLauncherBrowserTest : public ContentBrowserTest {};
 
 class StatsTableBrowserTest : public ChildProcessLauncherBrowserTest {
  public:
   void SetUpCommandLine(base::CommandLine* command_line) override {
     command_line->AppendSwitch(switches::kEnableStatsTable);
   }
 };
 
 IN_PROC_BROWSER_TEST_F(StatsTableBrowserTest, StartWithStatTable) {
   NavigateToURL(shell(), GURL("about:blank"));
 }
 
+IN_PROC_BROWSER_TEST_F(ChildProcessLauncherBrowserTest, ChildSpawnFail) {
+  GURL url("about:blank");
+  Shell* window = shell();
+  MockChildProcessLauncherClient* client(nullptr);
+
+  // Navigate once and simulate a process failing to spawn.
+  TestNavigationObserver nav_observer1(window->web_contents(), 1);
+  client = new MockChildProcessLauncherClient;
+  window->LoadURL(url);
+  client->client_ = static_cast<RenderProcessHostImpl*>(
+      window->web_contents()->GetRenderProcessHost())
+      ->child_process_launcher_->ReplaceClientForTest(client);
+  client->simulate_failure_ = true;
+  nav_observer1.Wait();
+  delete client;
+  NavigationEntry* last_entry =
+      shell()->web_contents()->GetController().GetLastCommittedEntry();
+  // Make sure we didn't navigate.
+  CHECK(!last_entry);
+
+  // Navigate again and let the process spawn correctly.
+  TestNavigationObserver nav_observer2(window->web_contents(), 1);
+  window->LoadURL(url);
+  nav_observer2.Wait();
+  last_entry = shell()->web_contents()->GetController().GetLastCommittedEntry();
+  // Make sure that we navigated to the proper URL.
+  CHECK(last_entry && last_entry->GetPageType() == PAGE_TYPE_NORMAL);
+  CHECK(shell()->web_contents()->GetLastCommittedURL() == url);
+
+  // Navigate again, using the same renderer.
+  url = GURL("data:text/html,dataurl");
+  TestNavigationObserver nav_observer3(window->web_contents(), 1);
+  window->LoadURL(url);
+  nav_observer3.Wait();
+  last_entry = shell()->web_contents()->GetController().GetLastCommittedEntry();
+  // Make sure that we navigated to the proper URL.
+  CHECK(last_entry && last_entry->GetPageType() == PAGE_TYPE_NORMAL);
+  CHECK(shell()->web_contents()->GetLastCommittedURL() == url);
+}
+
 }  // namespace content