StackFrameDepth should be managed per ThreadHeap

third_party/WebKit/Source/platform/heap/Heap.h

Index: third_party/WebKit/Source/platform/heap/Heap.h
diff --git a/third_party/WebKit/Source/platform/heap/Heap.h b/third_party/WebKit/Source/platform/heap/Heap.h
index 261b26e70bf4003fcc154cbee744b0fb8e642aff..b4238348c76ffbd059f349b64d672b3df2338440 100644
--- a/third_party/WebKit/Source/platform/heap/Heap.h
+++ b/third_party/WebKit/Source/platform/heap/Heap.h
@@ -35,6 +35,7 @@
 #include "platform/heap/GCInfo.h"
 #include "platform/heap/HeapPage.h"
 #include "platform/heap/PageMemory.h"
+#include "platform/heap/StackFrameDepth.h"
 #include "platform/heap/ThreadState.h"
 #include "platform/heap/Visitor.h"
 #include "wtf/AddressSanitizer.h"
@@ -231,6 +232,8 @@ public:
         return isHeapObjectAlive(ptr);
     }
 
+    StackFrameDepth& stackFrameDepth() { return m_stackFrameDepth; }
+
     RecursiveMutex& threadAttachMutex() { return m_threadAttachMutex; }
     const ThreadStateSet& threads() const { return m_threads; }
     ThreadHeapStats& heapStats() { return m_stats; }
@@ -412,6 +415,7 @@ private:
     std::unique_ptr<CallbackStack> m_globalWeakCallbackStack;
     std::unique_ptr<CallbackStack> m_ephemeronStack;
     BlinkGC::GCReason m_lastGCReason;
+    StackFrameDepth m_stackFrameDepth;
 
     static ThreadHeap* s_mainThreadHeap;