Guard use of Chrome TLS in GlobalActivityTracker::GetOrCreateTracker.

The implementation of heap_profiling uses base::Lock. That uses
GlobalActivityTracker::GetOrCreateTracker, which uses Chrome TLS. Since
heap_profiling may be used post TLS destruction, all called code must also guard
against use of Chrome TLS by checking
base::ThreadLocalStorage::HasBeenDestroyed.

Bug: 864589
Change-Id: I9b7b61d702a79062f847f17d18b6d30f3681b837
Reviewed-on: https://chromium-review.googlesource.com/1142347Reviewed-by: Gabriel Charette <gab@chromium.org>
Commit-Queue: Erik Chen <erikchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#576224}

base/debug/activity_tracker.h

@@ -860,6 +860,13 @@ class BASE_EXPORT GlobalActivityTracker {
       GlobalActivityTracker* global_tracker = Get();
       if (!global_tracker)
         return nullptr;
+
+      // It is not safe to use TLS once TLS has been destroyed. This can happen
+      // if code that runs late during thread destruction tries to use a
+      // base::Lock. See https://crbug.com/864589.
+      if (base::ThreadLocalStorage::HasBeenDestroyed())
+        return nullptr;
+
       if (lock_allowed)
         return global_tracker->GetOrCreateTrackerForCurrentThread();
       else

base/threading/thread_local_storage.h

@@ -30,6 +30,10 @@ namespace base {
 
 class SamplingHeapProfiler;
 
+namespace debug {
+class GlobalActivityTracker;
+}  // namespace debug
+
 namespace trace_event {
 class MallocDumpProvider;
 }  // namespace trace_event
@@ -160,6 +164,7 @@ class BASE_EXPORT ThreadLocalStorage {
   friend class base::SamplingHeapProfiler;
   friend class base::internal::ThreadLocalStorageTestInternal;
   friend class base::trace_event::MallocDumpProvider;
+  friend class debug::GlobalActivityTracker;
   friend class heap_profiling::ScopedAllowAlloc;
   friend class ui::TLSDestructionCheckerForX11;
   static bool HasBeenDestroyed();

components/services/heap_profiling/public/cpp/allocator_shim.cc

@@ -883,6 +883,9 @@ void AllocatorShimLogAlloc(AllocatorType type,
   }
 }
 
+// This function may be called post Chrome TLS destruction, so it must not use
+// Chrome TLS. It currently uses 3 classes from Chrome: base::Lock,
+// base::TimeTicks and base::ScopedPlatformFile, all of which are safe.
 void AllocatorShimLogFree(void* address) {
   SendBuffer* send_buffers = g_send_buffers.Read();
   if (!send_buffers)