[regexp] Add fast-path for global, callable replace

src/string-builder.h

 // Copyright 2014 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_STRING_BUILDER_H_
 #define V8_STRING_BUILDER_H_
 
 #include "src/assert-scope.h"
 #include "src/factory.h"
 #include "src/handles.h"
@@ skipping 156 matching lines @@
     array_->set(length_, value);
     length_++;
   }
 
   Handle<FixedArray> array() { return array_; }
 
   int length() { return length_; }
 
   int capacity() { return array_->length(); }
 
+  Handle<JSArray> ToJSArray(Handle<JSArray> target_array) {
+    JSArray::SetContent(target_array, array_);
+    target_array->set_length(Smi::FromInt(length_));
+    return target_array;
+  }
 
  private:
   Handle<FixedArray> array_;
   int length_;
   bool has_non_smi_elements_;
 };
 
 
 class ReplacementStringBuilder {
  public:
@@ skipping 245 matching lines @@
     DCHECK_EQ(String::TWO_BYTE_ENCODING, encoding_);
     SeqTwoByteString::cast(*current_part_)
         ->SeqTwoByteStringSet(current_index_++, c);
   }
   if (current_index_ == part_length_) Extend();
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_STRING_BUILDER_H_