Introduce safe interface to "copy and grow" FixedArray.

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 2001 matching lines @@
   MUST_USE_RESULT AllocationResult
       AllocateInternalizedStringImpl(T t, int chars, uint32_t hash_field);
 
   template <typename T>
   MUST_USE_RESULT inline AllocationResult AllocateInternalizedStringImpl(
       T t, int chars, uint32_t hash_field);
 
   // Allocates an uninitialized fixed array. It must be filled by the caller.
   MUST_USE_RESULT AllocationResult AllocateUninitializedFixedArray(int length);
 
-  // Make a copy of src and return it. Returns
-  // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed.
+  // Make a copy of src and return it.
   MUST_USE_RESULT inline AllocationResult CopyFixedArray(FixedArray* src);
 
-  // Make a copy of src, set the map, and return the copy. Returns
-  // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed.
+  // Make a copy of src, also grow the copy, and return the copy.
+  MUST_USE_RESULT AllocationResult
+      CopyFixedArrayAndGrow(FixedArray* src, int grow_by);
+
+  // Make a copy of src, set the map, and return the copy.
   MUST_USE_RESULT AllocationResult
       CopyFixedArrayWithMap(FixedArray* src, Map* map);
 
-  // Make a copy of src and return it. Returns
-  // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed.
+  // Make a copy of src and return it.
   MUST_USE_RESULT inline AllocationResult CopyFixedDoubleArray(
       FixedDoubleArray* src);
 
   // Computes a single character string where the character has code.
   // A cache is used for one-byte (Latin1) codes.
   MUST_USE_RESULT AllocationResult
       LookupSingleCharacterStringFromCode(uint16_t code);
 
   // Allocate a symbol in old space.
   MUST_USE_RESULT AllocationResult AllocateSymbol();
@@ skipping 785 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_