Remove task.h and finish base::Bind() migration.

chrome/browser/ui/gtk/browser_window_gtk.cc

Index: chrome/browser/ui/gtk/browser_window_gtk.cc
diff --git a/chrome/browser/ui/gtk/browser_window_gtk.cc b/chrome/browser/ui/gtk/browser_window_gtk.cc
index 98a68d1495b401df71db35cedf3b847be00b8695..8ce9b4709f3885f7a3bd4a11452a4301e52d85f9 100644
--- a/chrome/browser/ui/gtk/browser_window_gtk.cc
+++ b/chrome/browser/ui/gtk/browser_window_gtk.cc
@@ -22,7 +22,6 @@
 #include "base/nix/xdg_util.h"
 #include "base/path_service.h"
 #include "base/string_util.h"
-#include "base/task.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/app/chrome_command_ids.h"
@@ -1581,7 +1580,7 @@ void BrowserWindowGtk::OnMainWindowDestroy(GtkWidget* widget) {
   // We don't want to use DeleteSoon() here since it won't work on a nested pump
   // (like in UI tests).
   MessageLoop::current()->PostTask(
-      FROM_HERE, base::Bind(&DeletePointer<BrowserWindowGtk>, this));
+      FROM_HERE, base::Bind(&base::DeletePointer<BrowserWindowGtk>, this));
 }
 
 void BrowserWindowGtk::UnMaximize() {