Fix multi-isolate build:

src/ia32/regexp-macro-assembler-ia32.cc

 // Copyright 2008-2009 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 81 matching lines @@
  *              bool at_start,
  *              byte* stack_area_base,
  *              bool direct_call)
  */
 
 #define __ ACCESS_MASM(masm_)
 
 RegExpMacroAssemblerIA32::RegExpMacroAssemblerIA32(
     Mode mode,
     int registers_to_save)
-    : masm_(new MacroAssembler(NULL, kRegExpCodeSize)),
+    : masm_(new MacroAssembler(Isolate::Current(), NULL, kRegExpCodeSize)),
       mode_(mode),
       num_registers_(registers_to_save),
       num_saved_registers_(registers_to_save),
       entry_label_(),
       start_label_(),
       success_label_(),
       backtrack_label_(),
       exit_label_() {
   ASSERT_EQ(0, registers_to_save % 2);
   __ jmp(&entry_label_);   // We'll write the entry code later.
@@ skipping 1142 matching lines @@
 }
 
 
 #undef __
 
 #endif  // V8_INTERPRETED_REGEXP
 
 }}  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32