[TaskScheduler] Migrate a few more headers missed in //third_party

This is the //third_party equivalent to
https://chromium-review.googlesource.com/c/chromium/src/+/1161179
(DEPS tweak will soon be recovered to moved header in
https://chromium-review.googlesource.com/c/chromium/src/+/1161116)

TBR=skyostil@chromium.org

Bug: 867421
Change-Id: I607bf6caa71dda52e3290d59daaac568c2cba626
Reviewed-on: https://chromium-review.googlesource.com/1162639
Commit-Queue: Gabriel Charette <gab@chromium.org>
Reviewed-by: Gabriel Charette <gab@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580784}

third_party/blink/renderer/DEPS

@@ -22,7 +22,7 @@ include_rules = [
     "+base/stl_util.h",
     "+base/sys_byteorder.h",
     "+base/sys_info.h",
-    "+base/task_scheduler/post_task.h",
+    "+base/task/post_task_forward.h",
     "+base/test/scoped_feature_list.h",
     "+base/thread_annotations.h",
     "+base/threading/thread_checker.h",

third_party/blink/renderer/platform/blob/blob_bytes_provider.cc

@@ -5,7 +5,7 @@
 #include "third_party/blink/renderer/platform/blob/blob_bytes_provider.h"
 
 #include "base/numerics/safe_conversions.h"
-#include "base/task_scheduler/post_task.h"
+#include "base/task/post_task_forward.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
 #include "third_party/blink/public/platform/platform.h"
 #include "third_party/blink/public/platform/web_thread.h"

third_party/blink/renderer/platform/scheduler/DEPS

@@ -39,7 +39,7 @@ include_rules = [
   "+base/task/sequence_manager/sequence_manager.h",
   "+base/task/sequence_manager/task_queue.h",
   "+base/task/sequence_manager/time_domain.h",
-  "+base/task_scheduler/task_traits.h",
+  "+base/task/task_traits_forward.h",
   "+base/threading/platform_thread.h",
   "+base/threading/sequenced_task_runner_handle.h",
   "+base/threading/thread.h",

third_party/blink/renderer/platform/scheduler/common/background_scheduler.cc

@@ -5,7 +5,7 @@
 #include "third_party/blink/renderer/platform/scheduler/public/background_scheduler.h"
 
 #include "base/location.h"
-#include "base/task_scheduler/post_task.h"
+#include "base/task/post_task_forward.h"
 
 namespace blink {
 

third_party/blink/renderer/platform/scheduler/public/background_scheduler.h

@@ -7,7 +7,7 @@
 
 #include "base/location.h"
 #include "base/sequenced_task_runner.h"
-#include "base/task_scheduler/task_traits.h"
+#include "base/task/task_traits_forward.h"
 #include "third_party/blink/renderer/platform/platform_export.h"
 #include "third_party/blink/renderer/platform/wtf/functional.h"
 

third_party/webrtc_overrides/rtc_base/task_queue.cc

@@ -14,7 +14,7 @@
 #include "base/lazy_instance.h"
 #include "base/memory/ref_counted.h"
 #include "base/synchronization/waitable_event.h"
-#include "base/task_scheduler/post_task.h"
+#include "base/task/post_task_forward.h"
 #include "base/threading/thread_local.h"
 #include "build/build_config.h"
 #include "third_party/webrtc/rtc_base/refcount.h"