Require an isolate parameter for most external reference creation to

src/x64/assembler-x64.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 481 matching lines @@
   uint64_t supported_;
   uint64_t enabled_;
   uint64_t found_by_runtime_probing_;
 
   friend class Isolate;
 
   DISALLOW_COPY_AND_ASSIGN(CpuFeatures);
 };
 
 
-class Assembler : public Malloced {
+class Assembler : public AssemblerBase {
  private:
   // We check before assembling an instruction that there is sufficient
   // space to write an instruction and its relocation information.
   // The relocation writer's position must be kGap bytes above the end of
   // the generated instructions. This leaves enough space for the
   // longest possible x64 instruction, 15 bytes, and the longest possible
   // relocation information encoding, RelocInfoWriter::kMaxLength == 16.
   // (There is a 15 byte limit on x64 instruction length that rules out some
   // otherwise valid instructions.)
   // This allows for a single, fast space check per instruction.
@@ skipping 1094 matching lines @@
  private:
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_ASSEMBLER_X64_H_