[TaskScheduler]: Cleanup AssertBlockingAllowedDeprecated.

Migration is complete! Delete AssertBlockingAllowedDeprecated().

Bug: 903957
Change-Id: I683e879f8d1f07a1e38d2fa6bb1423101699fb68
Reviewed-on: https://chromium-review.googlesource.com/c/1474826
Commit-Queue: Etienne Pierre-Doray <etiennep@chromium.org>
Commit-Queue: François Doray <fdoray@chromium.org>
Reviewed-by: François Doray <fdoray@chromium.org>
Cr-Commit-Position: refs/heads/master@{#632680}

base/threading/thread_restrictions.cc

@@ -41,10 +41,6 @@ void AssertBlockingAllowed() {
 
 }  // namespace internal
 
-void AssertBlockingAllowedDeprecated() {
-  internal::AssertBlockingAllowed();
-}
-
 void DisallowBlocking() {
   g_blocking_disallowed.Get().Set(true);
 }

base/threading/thread_restrictions.h

@@ -291,14 +291,6 @@ INLINE_IF_DCHECK_IS_OFF void AssertBlockingAllowed()
 
 }  // namespace internal
 
-// Asserts that blocking calls are allowed in the current scope.
-//
-// DEPRECATED: Use ScopedBlockingCall, which serves as a precise annotation of
-// the scope that may/will block.
-// TODO(etiennep): Complete migration and delete this method.
-INLINE_IF_DCHECK_IS_OFF void AssertBlockingAllowedDeprecated()
-    EMPTY_BODY_IF_DCHECK_IS_OFF;
-
 // Disallows blocking on the current thread.
 INLINE_IF_DCHECK_IS_OFF void DisallowBlocking() EMPTY_BODY_IF_DCHECK_IS_OFF;