Remove base/thread_task_runner_handle.h dummy.

base/BUILD.gn

 # Copyright (c) 2013 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.
 
 # HOW TO WRITE CONDITIONALS IN THIS FILE
 # ======================================
 #
 # In many other places, one would write a conditional that expresses all the
 # cases when a source file is used or unused, and then either add or subtract
 # it from the sources list in that case
@@ skipping 777 matching lines @@
     "task_scheduler/task_traits.h",
     "template_util.h",
     "third_party/dmg_fp/dmg_fp.h",
     "third_party/dmg_fp/dtoa_wrapper.cc",
     "third_party/dmg_fp/g_fmt.cc",
     "third_party/icu/icu_utf.cc",
     "third_party/icu/icu_utf.h",
     "third_party/nspr/prtime.cc",
     "third_party/nspr/prtime.h",
     "third_party/superfasthash/superfasthash.c",
-    "thread_task_runner_handle.h",
     "threading/non_thread_safe.h",
     "threading/non_thread_safe_impl.cc",
     "threading/non_thread_safe_impl.h",
     "threading/platform_thread.h",
     "threading/platform_thread_android.cc",
     "threading/platform_thread_internal_posix.cc",
     "threading/platform_thread_internal_posix.h",
     "threading/platform_thread_linux.cc",
     "threading/platform_thread_mac.mm",
     "threading/platform_thread_posix.cc",
@@ skipping 1566 matching lines @@
 
   # GYP: //base.gyp:base_java_unittest_support
   android_library("base_java_unittest_support") {
     deps = [
       ":base_java",
     ]
     java_files =
         [ "test/android/java/src/org/chromium/base/ContentUriTestUtils.java" ]
   }
 }