Remove a bunch of Isolate::Current() callsites from simulators

src/arm64/simulator-arm64.cc

Index: src/arm64/simulator-arm64.cc
diff --git a/src/arm64/simulator-arm64.cc b/src/arm64/simulator-arm64.cc
index 4e6a9d91e1a99d323b3094b8bc486ef954397834..93ea37a0e2ef516cad4bd09e0422915da84ab8ff 100644
--- a/src/arm64/simulator-arm64.cc
+++ b/src/arm64/simulator-arm64.cc
@@ -462,13 +462,11 @@ void Simulator::RunFrom(Instruction* start) {
 // offset from the svc instruction so the simulator knows what to call.
 class Redirection {
  public:
-  Redirection(void* external_function, ExternalReference::Type type)
-      : external_function_(external_function),
-        type_(type),
-        next_(NULL) {
+  Redirection(Isolate* isolate, void* external_function,
+              ExternalReference::Type type)
+      : external_function_(external_function), type_(type), next_(NULL) {
     redirect_call_.SetInstructionBits(
         HLT | Assembler::ImmException(kImmExceptionIsRedirectedCall));
-    Isolate* isolate = Isolate::Current();
     next_ = isolate->simulator_redirection();
     // TODO(all): Simulator flush I cache
     isolate->set_simulator_redirection(this);
@@ -483,9 +481,8 @@ class Redirection {
 
   ExternalReference::Type type() { return type_; }
 
-  static Redirection* Get(void* external_function,
+  static Redirection* Get(Isolate* isolate, void* external_function,
                           ExternalReference::Type type) {
-    Isolate* isolate = Isolate::Current();
     Redirection* current = isolate->simulator_redirection();
     for (; current != NULL; current = current->next_) {
       if (current->external_function_ == external_function) {
@@ -493,7 +490,7 @@ class Redirection {
         return current;
       }
     }
-    return new Redirection(external_function, type);
+    return new Redirection(isolate, external_function, type);
   }
 
   static Redirection* FromHltInstruction(Instruction* redirect_call) {
@@ -748,9 +745,10 @@ void Simulator::DoRuntimeCall(Instruction* instr) {
 }
 
 
-void* Simulator::RedirectExternalReference(void* external_function,
+void* Simulator::RedirectExternalReference(Isolate* isolate,
+                                           void* external_function,
                                            ExternalReference::Type type) {
-  Redirection* redirection = Redirection::Get(external_function, type);
+  Redirection* redirection = Redirection::Get(isolate, external_function, type);
   return redirection->address_of_redirect_call();
 }
 
@@ -3510,7 +3508,7 @@ void Simulator::Debug() {
                  reinterpret_cast<uint64_t>(cur), *cur, *cur);
           HeapObject* obj = reinterpret_cast<HeapObject*>(*cur);
           int64_t value = *cur;
-          Heap* current_heap = v8::internal::Isolate::Current()->heap();
+          Heap* current_heap = isolate_->heap();
           if (((value & 1) == 0) || current_heap->Contains(obj)) {
             PrintF(" (");
             if ((value & kSmiTagMask) == 0) {