Fix flakiness in FlashPermissionBrowserTest.BlockFileURL with PlzNavigate after r460581.

chrome/browser/plugins/flash_permission_browsertest.cc

 // Copyright 2016 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/base_switches.h"
 #include "base/command_line.h"
 #include "base/memory/ptr_util.h"
 #include "base/path_service.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/permissions/permissions_browsertest.h"
@@ skipping 55 matching lines @@
 
   void TriggerPrompt() override {
     if (prompt_factory()->response_type() ==
         PermissionRequestManager::ACCEPT_ALL) {
       // If the prompt will be allowed, we need to wait for the page to refresh.
       PageReloadWaiter reload_waiter(GetWebContents());
       EXPECT_TRUE(RunScriptReturnBool("triggerPrompt();"));
       EXPECT_TRUE(reload_waiter.Wait());
     } else {
       EXPECT_TRUE(RunScriptReturnBool("triggerPrompt();"));
+      // Make a round trip to the renderer to flush any old did stop IPCs,
+      // otherwise they can race with the next navigation and cause it to be
+      // cancelled if it's the same URL.
+      EXPECT_TRUE(ExecuteScript(GetWebContents(), std::string()));
     }
   }
 
   bool FeatureUsageSucceeds() override {
     // If flash should have been blocked, reload the page to be sure that it is
     // blocked.
     //
     // NB: In cases where flash is allowed the page reloads automatically,
     // and tests should always wait for that reload to finish before calling
     // this method.
     ui_test_utils::NavigateToURL(browser(),
                                  GetWebContents()->GetLastCommittedURL());
     // If either flash with or without fallback content runs successfully it
     // indicates the feature is at least partly working, which could imply a
     // faulty permission.
     return RunScriptReturnBool("flashIsEnabled();") ||
            RunScriptReturnBool("flashIsEnabledForPluginWithoutFallback();");
   }
 };
 
 IN_PROC_BROWSER_TEST_F(FlashPermissionBrowserTest,
                        CommonFailsBeforeRequesting) {
   CommonFailsBeforeRequesting();
 }
 
 IN_PROC_BROWSER_TEST_F(FlashPermissionBrowserTest, CommonFailsIfDismissed) {
   CommonFailsIfDismissed();
 }
 
-// https://crbug.com/706780
-IN_PROC_BROWSER_TEST_F(FlashPermissionBrowserTest,
-                       DISABLED_CommonFailsIfBlocked) {
+IN_PROC_BROWSER_TEST_F(FlashPermissionBrowserTest, CommonFailsIfBlocked) {
   CommonFailsIfBlocked();
 }
 
 IN_PROC_BROWSER_TEST_F(FlashPermissionBrowserTest, CommonSucceedsIfAllowed) {
   CommonSucceedsIfAllowed();
 }
 
 IN_PROC_BROWSER_TEST_F(FlashPermissionBrowserTest, SucceedsInPopupWindow) {
   // Spawn the same page in a popup window and wait for it to finish loading.
   content::WebContents* original_contents = GetWebContents();
@@ skipping 81 matching lines @@
   CommonSucceedsIfAllowed();
   EXPECT_EQ(1, prompt_factory()->total_request_count());
 
   // Navigate to a second URL to verify it's allowed on all file: URLs.
   ui_test_utils::NavigateToURL(
       browser(),
       GURL("file://" + test_path.AsUTF8Unsafe() + "/permissions/flash2.html"));
   EXPECT_TRUE(FeatureUsageSucceeds());
 }
 
-// Failing often. http://crbug.com/706780.
-IN_PROC_BROWSER_TEST_F(FlashPermissionBrowserTest, DISABLED_BlockFileURL) {
+IN_PROC_BROWSER_TEST_F(FlashPermissionBrowserTest, BlockFileURL) {
   base::FilePath test_path;
   PathService::Get(chrome::DIR_TEST_DATA, &test_path);
   ui_test_utils::NavigateToURL(
       browser(), GURL("file://" + test_path.AsUTF8Unsafe() + test_url()));
   CommonFailsIfBlocked();
   EXPECT_EQ(1, prompt_factory()->total_request_count());
 
   // Navigate to a second URL to verify it's blocked on all file: URLs.
   ui_test_utils::NavigateToURL(
       browser(),
       GURL("file://" + test_path.AsUTF8Unsafe() + "/permissions/flash2.html"));
   EXPECT_FALSE(FeatureUsageSucceeds());
 }