[heap] Remove heap-local variable caching FLAG_concurrent_sweeping

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index c6ebc0dccea50d4bb4eae4fe8e346b2c1a9282d5..aa65e8d78adb662ca4b3a41d48e2c1e90fec8ace 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -162,7 +162,6 @@ Heap::Heap()
       pending_unmapping_tasks_semaphore_(0),
       gc_callbacks_depth_(0),
       deserialization_complete_(false),
-      concurrent_sweeping_enabled_(false),
       strong_roots_list_(NULL),
       array_buffer_tracker_(NULL) {
 // Allow build-time customization of the max semispace size. Building
@@ -5004,8 +5003,6 @@ bool Heap::SetUp() {
     if (!ConfigureHeapDefault()) return false;
   }
 
-  concurrent_sweeping_enabled_ = FLAG_concurrent_sweeping;
-
   base::CallOnce(&initialize_gc_once, &InitializeGCOnce);
 
   // Set up memory allocator.