Verify a bit more about external strings

src/heap/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_HEAP_H_
 #define V8_HEAP_HEAP_H_
 
 #include <cmath>
 #include <map>
 
@@ skipping 743 matching lines @@
   // Strict mode arguments has no callee so it is smaller.
   static const int kStrictArgumentsObjectSize =
       JSObject::kHeaderSize + 1 * kPointerSize;
   // Indicies for direct access into argument objects.
   static const int kArgumentsLengthIndex = 0;
   // callee is only valid in sloppy mode.
   static const int kArgumentsCalleeIndex = 1;
 
   // Finalizes an external string by deleting the associated external
   // data and clearing the resource pointer.
-  inline void FinalizeExternalString(String* string);
+  void FinalizeExternalString(String* string);
 
   // Initialize a filler object to keep the ability to iterate over the heap
   // when introducing gaps within pages.
   void CreateFillerObjectAt(Address addr, int size);
 
   bool CanMoveObjectStart(HeapObject* object);
 
   // Indicates whether live bytes adjustment is triggered
   // - from within the GC code before sweeping started (SEQUENTIAL_TO_SWEEPER),
   // - or from within GC (CONCURRENT_TO_SWEEPER),
@@ skipping 1952 matching lines @@
   DisallowHeapAllocation no_allocation;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_HEAP_H_