Reland "Don't compile functions in a context the caller doesn't have access to"

src/isolate.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/isolate.h"
 
 #include <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
@@ skipping 2869 matching lines @@
     heap()->set_microtask_queue(heap()->empty_fixed_array());
 
     Isolate* isolate = this;
     FOR_WITH_HANDLE_SCOPE(isolate, int, i = 0, i, i < num_tasks, i++, {
       Handle<Object> microtask(queue->get(i), this);
       if (microtask->IsJSFunction()) {
         Handle<JSFunction> microtask_function =
             Handle<JSFunction>::cast(microtask);
         SaveContext save(this);
         set_context(microtask_function->context()->native_context());
+        handle_scope_implementer_->EnterContext(
+            handle(microtask_function->context(), this));
         MaybeHandle<Object> maybe_exception;
         MaybeHandle<Object> result = Execution::TryCall(
             this, microtask_function, factory()->undefined_value(), 0, NULL,
             &maybe_exception);
+        handle_scope_implementer_->LeaveContext();
         // If execution is terminating, just bail out.
         Handle<Object> exception;
         if (result.is_null() && maybe_exception.is_null()) {
           // Clear out any remaining callbacks in the queue.
           heap()->set_microtask_queue(heap()->empty_fixed_array());
           set_pending_microtask_count(0);
           return;
         }
       } else {
         Handle<CallHandlerInfo> callback_info =
@@ skipping 181 matching lines @@
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8