Here's the diff of the fixit output:
$ git diff origin/master -- third_party/WebKit/Source/platform/scheduler/base/task_queue_manager.cc
diff --git a/third_party/WebKit/Source/platform/scheduler/base/task_queue_manager.cc b/third_party/WebKit/Source/platform/scheduler/base/task_queue_manager.cc
index 31d3816ac814..88623cb7e637 100644
--- a/third_party/WebKit/Source/platform/scheduler/base/task_queue_manager.cc
+++ b/third_party/WebKit/Source/platform/scheduler/base/task_queue_manager.cc
@@ -617,7 +617,7 @@ LazyNow TaskQueueManager::CreateLazyNow() const {

 size_t TaskQueueManager::GetNumberOfPendingTasks() const {
   size_t task_count = 0;
-  for (auto& queue : active_queues_)
+  for (auto*& queue : active_queues_)
     task_count += queue->GetNumberOfPendingTasks();
   return task_count;
 }
@@ -631,7 +631,7 @@ TaskQueueManager::AsValueWithSelectorResult(
       new base::trace_event::TracedValue());
   base::TimeTicks now = real_time_domain()->CreateLazyNow().Now();
   state->BeginArray("active_queues");
-  for (auto& queue : active_queues_)
+  for (auto*& queue : active_queues_)
     queue->AsValueInto(now, state.get());
   state->EndArray();
   state->BeginArray("queues_to_delete");
@@ -703,7 +703,7 @@ void SweepCanceledDelayedTasksInQueue(

 void TaskQueueManager::SweepCanceledDelayedTasks() {
   std::map<TimeDomain*, base::TimeTicks> time_domain_now;
-  for (const auto& queue : active_queues_)
+  for (auto* const queue : active_queues_)
     SweepCanceledDelayedTasksInQueue(queue, &time_domain_now);
 }

Here's the build error:
gen/third_party/WebKit/Source/platform/scheduler/base/../../../../../../../../../third_party/WebKit/Source/platform/scheduler/base/task_queue_manager.cc:620:15: error: variable 'queue' with type 'auto *&' has incompatible initializer of type 'const std::__1::__tree_const_iterator<blink::scheduler::internal::TaskQueueImpl *, std::__1::__tree_node<blink::scheduler::internal::TaskQueueImpl *, void *> *, long>::value_type' (aka 'blink::scheduler::internal::TaskQueueImpl *const')                                                                                                                                                       
  for (auto*& queue : active_queues_)                                                                                                                                                                             
              ^     ~                                                                                                                                                                                             ../../buildtools/third_party/libc++/trunk/include/set:550:20: note: selected 'begin' function with iterator type 'std::__1::set<blink::scheduler::internal::TaskQueueImpl *, std::__1::less<blink::scheduler::internal::TaskQueueImpl *>, std::__1::allocator<blink::scheduler::internal::TaskQueueImpl *> >::const_iterator' (aka '__tree_const_iterator<blink::scheduler::internal::TaskQueueImpl *, std::__1::__tree_node<blink::scheduler::internal::TaskQueueImpl *, void *> *, long>')                                                                                                                                                              const_iterator begin() const _NOEXCEPT {return __tree_.begin();}                                                                                                                                              
                   ^                                                                                                                                                                                              In file included from gen/third_party/WebKit/Source/platform/scheduler/base/scheduler_jumbo_1.cc:13:                                                                                                              gen/third_party/WebKit/Source/platform/scheduler/base/../../../../../../../../../third_party/WebKit/Source/platform/scheduler/base/task_queue_manager.cc:634:15: error: variable 'queue' with type 'auto *&' has incompatible initializer of type 'const std::__1::__tree_const_iterator<blink::scheduler::internal::TaskQueueImpl *, std::__1::__tree_node<blink::scheduler::internal::TaskQueueImpl *, void *> *, long>::value_type' (aka 'blink::scheduler::internal::TaskQueueImpl *const')                                                                                                                                                       
  for (auto*& queue : active_queues_)                                                                                                                                                                             
              ^     ~                                                                                                                                                                                             ../../buildtools/third_party/libc++/trunk/include/set:550:20: note: selected 'begin' function with iterator type 'std::__1::set<blink::scheduler::internal::TaskQueueImpl *, std::__1::less<blink::scheduler::internal::TaskQueueImpl *>, std::__1::allocator<blink::scheduler::internal::TaskQueueImpl *> >::const_iterator' (aka '__tree_const_iterator<blink::scheduler::internal::TaskQueueImpl *, std::__1::__tree_node<blink::scheduler::internal::TaskQueueImpl *, void *> *, long>')
    const_iterator begin() const _NOEXCEPT {return __tree_.begin();}
                   ^

This was with a jumbo build. There's a few quirks of jumbo build that seem to cause it to emit incorrect replacements, so it's possible this could be another example of that.