Introduce per-isolate assert scopes and API to guard JS execution.

src/builtins.cc

 // Copyright 2012 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 1629 matching lines @@
       ASSERT(!masm.has_frame());
       g(&masm, functions[i].name, functions[i].extra_args);
       // Move the code into the object heap.
       CodeDesc desc;
       masm.GetCode(&desc);
       Code::Flags flags =  functions[i].flags;
       Object* code = NULL;
       {
         // During startup it's OK to always allocate and defer GC to later.
         // This simplifies things because we don't need to retry.
-        AlwaysAllocateScope __scope__;
+        AlwaysAllocateScope __scope__(isolate);
         { MaybeObject* maybe_code =
               heap->CreateCode(desc, flags, masm.CodeObject());
           if (!maybe_code->ToObject(&code)) {
             v8::internal::V8::FatalProcessOutOfMemory("CreateCode");
           }
         }
       }
       // Log the event and add the code to the builtins array.
       PROFILE(isolate,
               CodeCreateEvent(Logger::BUILTIN_TAG,
@@ skipping 77 matching lines @@
 }
 BUILTIN_LIST_C(DEFINE_BUILTIN_ACCESSOR_C)
 BUILTIN_LIST_A(DEFINE_BUILTIN_ACCESSOR_A)
 BUILTIN_LIST_H(DEFINE_BUILTIN_ACCESSOR_H)
 BUILTIN_LIST_DEBUG_A(DEFINE_BUILTIN_ACCESSOR_A)
 #undef DEFINE_BUILTIN_ACCESSOR_C
 #undef DEFINE_BUILTIN_ACCESSOR_A
 
 
 } }  // namespace v8::internal