[api] Clean up scopes and precheck instantiations cache

src/isolate.cc

Index: src/isolate.cc
diff --git a/src/isolate.cc b/src/isolate.cc
index cc8c8b6739f2fd6b9739dbc98e699e693d5bcc62..3b1db444aaac972bb57c29a9db792d6330be158f 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -3169,24 +3169,6 @@ bool StackLimitCheck::JsHasOverflowed(uintptr_t gap) const {
   return GetCurrentStackPosition() - gap < stack_guard->real_climit();
 }
 
-
-SaveContext::SaveContext(Isolate* isolate)
-    : isolate_(isolate), prev_(isolate->save_context()) {
-  if (isolate->context() != NULL) {
-    context_ = Handle<Context>(isolate->context());
-  }
-  isolate->set_save_context(this);
-
-  c_entry_fp_ = isolate->c_entry_fp(isolate->thread_local_top());
-}
-
-
-SaveContext::~SaveContext() {
-  isolate_->set_context(context_.is_null() ? NULL : *context_);
-  isolate_->set_save_context(prev_);
-}
-
-
 #ifdef DEBUG
 AssertNoContextChange::AssertNoContextChange(Isolate* isolate)
     : isolate_(isolate), context_(isolate->context(), isolate) {}