Revert "VM: [Kernel] elide parent context setup if it's empty"

runtime/vm/kernel_to_il.cc

Index: runtime/vm/kernel_to_il.cc
diff --git a/runtime/vm/kernel_to_il.cc b/runtime/vm/kernel_to_il.cc
index 6d95f78172a293f71ad406982c9b9860b78493df..9f2d4601307fbe47a96f02a3a28c0840969d7750 100644
--- a/runtime/vm/kernel_to_il.cc
+++ b/runtime/vm/kernel_to_il.cc
@@ -2311,23 +2311,14 @@ Fragment FlowGraphBuilder::AdjustContextTo(int depth) {
 }
 
 
-bool FlowGraphBuilder::HasContextScope() const {
-  const ContextScope& context_scope =
-      ContextScope::Handle(parsed_function_->function().context_scope());
-  return !context_scope.IsNull() && context_scope.num_variables() > 0;
-}
-
-
 Fragment FlowGraphBuilder::PushContext(int size) {
   ASSERT(size > 0);
   Fragment instructions = AllocateContext(size);
-  if (context_depth_ != 0 || HasContextScope()) {
-    LocalVariable* context = MakeTemporary();
-    instructions += LoadLocal(context);
-    instructions += LoadLocal(parsed_function_->current_context_var());
-    instructions +=
-        StoreInstanceField(TokenPosition::kNoSource, Context::parent_offset());
-  }
+  LocalVariable* context = MakeTemporary();
+  instructions += LoadLocal(context);
+  instructions += LoadLocal(parsed_function_->current_context_var());
+  instructions +=
+      StoreInstanceField(TokenPosition::kNoSource, Context::parent_offset());
   instructions += StoreLocal(TokenPosition::kNoSource,
                              parsed_function_->current_context_var());
   ++context_depth_;