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

content/browser/browser_thread_unittest.cc

Index: content/browser/browser_thread_unittest.cc
diff --git a/content/browser/browser_thread_unittest.cc b/content/browser/browser_thread_unittest.cc
index 458f8724a5268fe8d133de7e55daf4fff3be5191..6bb8e5aad985e2b84a005a7333e7b4e5900737e8 100644
--- a/content/browser/browser_thread_unittest.cc
+++ b/content/browser/browser_thread_unittest.cc
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/bind.h"
+#include "base/bind_helpers.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/message_loop_proxy.h"
@@ -38,9 +39,6 @@ class BrowserThreadTest : public testing::Test {
     message_loop->PostTask(FROM_HERE, MessageLoop::QuitClosure());
   }
 
-  static void DoNothing() {
-  }
-
   class DeletedOnFile
       : public base::RefCountedThreadSafe<
             DeletedOnFile, BrowserThread::DeleteOnFileThread> {
@@ -119,7 +117,7 @@ TEST_F(BrowserThreadTest, PostTaskAndReply) {
   ASSERT_TRUE(BrowserThread::PostTaskAndReply(
       BrowserThread::FILE,
       FROM_HERE,
-      base::Bind(&BrowserThreadTest::DoNothing),
+      base::Bind(&base::DoNothing),
       base::Bind(&MessageLoop::Quit,
                  base::Unretained(MessageLoop::current()->current()))));
   MessageLoop::current()->Run();