Throw exception on invalid string length instead of OOM.

src/factory.cc

 // Copyright 2013 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 359 matching lines @@
 
   if (length == 2) {
     uint16_t c1 = left->Get(0);
     uint16_t c2 = right->Get(0);
     return MakeOrFindTwoCharacterString(isolate(), c1, c2);
   }
 
   // Make sure that an out of memory exception is thrown if the length
   // of the new cons string is too large.
   if (length > String::kMaxLength || length < 0) {
-    isolate()->context()->mark_out_of_memory();
-    V8::FatalProcessOutOfMemory("String concatenation result too large.");
-    UNREACHABLE();
+    isolate()->ThrowInvalidStringLength();
     return Handle<String>::null();
   }
 
   bool left_is_one_byte = left->IsOneByteRepresentation();
   bool right_is_one_byte = right->IsOneByteRepresentation();
   bool is_one_byte = left_is_one_byte && right_is_one_byte;
   bool is_one_byte_data_in_two_byte_string = false;
   if (!is_one_byte) {
     // At least one of the strings uses two-byte representation so we
     // can't use the fast case code for short ASCII strings below, but
@@ skipping 1641 matching lines @@
   return Handle<Object>::null();
 }
 
 
 Handle<Object> Factory::ToBoolean(bool value) {
   return value ? true_value() : false_value();
 }
 
 
 } }  // namespace v8::internal