HeapCompact does not need to look up other threads' states

third_party/WebKit/Source/platform/heap/HeapCompact.cpp

Index: third_party/WebKit/Source/platform/heap/HeapCompact.cpp
diff --git a/third_party/WebKit/Source/platform/heap/HeapCompact.cpp b/third_party/WebKit/Source/platform/heap/HeapCompact.cpp
index cd95f8c6792aec83fecb30fdee89a791830a6522..995a7d81ee7da83caecf3a89a4a87cc1c74d825c 100644
--- a/third_party/WebKit/Source/platform/heap/HeapCompact.cpp
+++ b/third_party/WebKit/Source/platform/heap/HeapCompact.cpp
@@ -303,18 +303,12 @@ bool HeapCompact::shouldCompact(ThreadState* state,
       reason != BlinkGC::ForcedGC)
     return false;
 
-  const ThreadHeap& heap = state->heap();
-  // If any of the participating threads require a stack scan,
-  // do not compact.
-  //
+  // If the GCing thread requires a stack scan, do not compact.
   // Why? Should the stack contain an iterator pointing into its
   // associated backing store, its references wouldn't be
   // correctly relocated.
-  for (ThreadState* state : heap.threads()) {
-    if (state->stackState() == BlinkGC::HeapPointersOnStack) {
-      return false;
-    }
-  }
+  if (state->stackState() == BlinkGC::HeapPointersOnStack)
+    return false;
 
   // Compaction enable rules:
   //  - It's been a while since the last time.