Use thread_local vs ThreadLocal in FilePoller

Summary:
[Wangle] Use `thread_local` vs `ThreadLocal` in `FilePoller` to avoid something that looks like a DOF issue.

(Note: this ignores all push blocking failures!)

Reviewed By: yfeldblum

Differential Revision: D19791123

fbshipit-source-id: f7443c2332faabf28956ee6e5850781e62c2011d

Author: dmm-fb

wangle/util/FilePoller.cpp

@@ -56,9 +56,11 @@ folly::Singleton<PollerContext> contextSingleton([] {
 });
 }
 
-folly::ThreadLocal<bool> FilePoller::ThreadProtector::polling_([] {
-  return new bool(false);
-});
+bool* FilePoller::ThreadProtector::polling() {
+  static thread_local bool sPolling{false};
+  return &sPolling;
+}
+
 
 constexpr std::chrono::milliseconds FilePoller::kDefaultPollInterval;
 

wangle/util/FilePoller.h

@@ -160,15 +160,16 @@ class FilePoller {
   class ThreadProtector {
    public:
     ThreadProtector() {
-      *polling_ = true;
+     *polling() = true;
     }
     ~ThreadProtector() {
-      *polling_ = false;
+      *polling() = false;
     }
     static bool inPollerThread() {
-      return *polling_;
+      return *polling();
     }
-    static folly::ThreadLocal<bool> polling_;
+private:
+    static bool* polling();
   };
 };
 }