ScheduleLateNodeVisitor: check if dominator block is marked

R=mstarzinger@chromium.org

Change-Id: Ifc6411f4825b5056ab35f9b7d0a604bed4004110
Reviewed-on: https://chromium-review.googlesource.com/c/1337732Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57545}

src/compiler/scheduler.cc

@@ -1524,7 +1524,7 @@ class ScheduleLateNodeVisitor {
       if (!scheduler_->IsLive(edge.from())) continue;
       BasicBlock* use_block = GetBlockForUse(edge);
       if (use_block == nullptr) continue;
-      while (IsMarked(use_block)) {
+      while (IsMarked(use_block->dominator())) {
         use_block = use_block->dominator();
       }
       auto& use_node = dominators[use_block];