[TaskScheduler] Remove temporary forwarding headers and mass migrate users

When this CL is approved I will rebase it on top of tree and mass
migrate all callers in a new patch set (TBR'ed change).

[email protected] (for mass migration of existing callers)

Bug: 867421
Change-Id: I41092bbc4824964ee047e0bf53e972c8f6e896a4
Reviewed-on: https://chromium-review.googlesource.com/1161116
Commit-Queue: Gabriel Charette <[email protected]>
Reviewed-by: Gabriel Charette <[email protected]>
Reviewed-by: Sami Kyöstilä <[email protected]>
Cr-Commit-Position: refs/heads/master@{#580845}
diff --git a/components/update_client/component_patcher_operation.cc b/components/update_client/component_patcher_operation.cc
index de1a5dc..b3a1ec1c 100644
--- a/components/update_client/component_patcher_operation.cc
+++ b/components/update_client/component_patcher_operation.cc
@@ -13,7 +13,7 @@
 #include "base/files/memory_mapped_file.h"
 #include "base/location.h"
 #include "base/strings/string_number_conversions.h"
-#include "base/task/post_task_forward.h"
+#include "base/task/post_task.h"
 #include "base/threading/sequenced_task_runner_handle.h"
 #include "components/services/patch/public/cpp/patch.h"
 #include "components/update_client/update_client.h"