Disentangle assembler from isolate.

src/ia32/macro-assembler-ia32.h

Index: src/ia32/macro-assembler-ia32.h
diff --git a/src/ia32/macro-assembler-ia32.h b/src/ia32/macro-assembler-ia32.h
index 984b051b91323ec707c7ed566e599c2eec6a30e4..8b04f5b6380987d5f6162884561fe1b3315f1941 100644
--- a/src/ia32/macro-assembler-ia32.h
+++ b/src/ia32/macro-assembler-ia32.h
@@ -57,6 +57,10 @@ class MacroAssembler: public Assembler {
   MacroAssembler(Isolate* isolate, void* buffer, int size,
                  CodeObjectRequired create_code_object);
 
+  int jit_cookie() const { return jit_cookie_; }
+
+  Isolate* isolate() const { return isolate_; }
+
   void Load(Register dst, const Operand& src, Representation r);
   void Store(Register src, const Operand& dst, Representation r);
 
@@ -880,8 +884,10 @@ class MacroAssembler: public Assembler {
  private:
   bool generating_stub_;
   bool has_frame_;
+  Isolate* isolate_;
   // This handle will be patched with the code object on installation.
   Handle<Object> code_object_;
+  int jit_cookie_;
 
   // Helper functions for generating invokes.
   void InvokePrologue(const ParameterCount& expected,