Diagnose EscapingMouseLockAndFullscreen test timing out.

chrome/browser/ui/fullscreen/fullscreen_controller_interactive_browsertest.cc

Index: chrome/browser/ui/fullscreen/fullscreen_controller_interactive_browsertest.cc
diff --git a/chrome/browser/ui/fullscreen/fullscreen_controller_interactive_browsertest.cc b/chrome/browser/ui/fullscreen/fullscreen_controller_interactive_browsertest.cc
index 0ba098ea8d6ca02c7ccf289c7d59276802049e6f..a49a5e63b18a2d78c802922704d7ada4b174f515 100644
--- a/chrome/browser/ui/fullscreen/fullscreen_controller_interactive_browsertest.cc
+++ b/chrome/browser/ui/fullscreen/fullscreen_controller_interactive_browsertest.cc
@@ -96,10 +96,12 @@ IN_PROC_BROWSER_TEST_F(FullscreenControllerInteractiveTest,
   // Request to lock the mouse and enter fullscreen.
   {
     FullscreenNotificationObserver fullscreen_observer;
+fprintf(stderr, "%s:%s:%d\n", __FILE__, __FUNCTION__, __LINE__);
     ASSERT_TRUE(ui_test_utils::SendKeyPressAndWait(
         browser(), ui::VKEY_B, false, true, false, false,
         chrome::NOTIFICATION_MOUSE_LOCK_CHANGED,
         content::NotificationService::AllSources()));
+fprintf(stderr, "%s:%s:%d\n", __FILE__, __FUNCTION__, __LINE__);
     fullscreen_observer.Wait();
   }
   ASSERT_TRUE(IsFullscreenPermissionRequested());
@@ -109,6 +111,7 @@ IN_PROC_BROWSER_TEST_F(FullscreenControllerInteractiveTest,
   {
     FullscreenNotificationObserver fullscreen_observer;
     SendEscapeToFullscreenController();
+fprintf(stderr, "%s:%s:%d\n", __FILE__, __FUNCTION__, __LINE__);
     fullscreen_observer.Wait();
   }
   ASSERT_FALSE(IsFullscreenPermissionRequested());
@@ -117,10 +120,12 @@ IN_PROC_BROWSER_TEST_F(FullscreenControllerInteractiveTest,
   // Request to lock the mouse and enter fullscreen.
   {
     FullscreenNotificationObserver fullscreen_observer;
+fprintf(stderr, "%s:%s:%d\n", __FILE__, __FUNCTION__, __LINE__);
     ASSERT_TRUE(ui_test_utils::SendKeyPressAndWait(
         browser(), ui::VKEY_B, false, true, false, false,
         chrome::NOTIFICATION_MOUSE_LOCK_CHANGED,
         content::NotificationService::AllSources()));
+fprintf(stderr, "%s:%s:%d\n", __FILE__, __FUNCTION__, __LINE__);
     fullscreen_observer.Wait();
   }
   ASSERT_TRUE(IsFullscreenPermissionRequested());
@@ -137,6 +142,7 @@ IN_PROC_BROWSER_TEST_F(FullscreenControllerInteractiveTest,
   {
     FullscreenNotificationObserver fullscreen_observer;
     SendEscapeToFullscreenController();
+fprintf(stderr, "%s:%s:%d\n", __FILE__, __FUNCTION__, __LINE__);
     fullscreen_observer.Wait();
   }
   ASSERT_FALSE(IsMouseLocked());