Object.observe: Move notification of JSArray length changes to JSArray::SetElementsLength

src/objects.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 8363 matching lines @@
   MUST_USE_RESULT MaybeObject* JSArrayUpdateLengthFromIndex(uint32_t index,
                                                             Object* value);
 
   // Initialize the array with the given capacity. The function may
   // fail due to out-of-memory situations, but only if the requested
   // capacity is non-zero.
   MUST_USE_RESULT MaybeObject* Initialize(int capacity);
 
   // Initializes the array to a certain length.
   inline bool AllowsSetElementsLength();
+  // Can cause GC.
   MUST_USE_RESULT MaybeObject* SetElementsLength(Object* length);
 
   // Set the content of the array to the content of storage.
   MUST_USE_RESULT inline MaybeObject* SetContent(FixedArrayBase* storage);
 
   // Casting.
   static inline JSArray* cast(Object* obj);
 
   // Uses handles.  Ensures that the fixed array backing the JSArray has at
   // least the stated size.
@@ skipping 642 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_