[Kernel] replace function debuggable field with originalAsyncMarker field

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 d12987fae7982f10fa0cbd485b18b8f52d3299b7..942a70f5e26ad0f46503d782cda6fcf3f37cdfd8 100644
--- a/runtime/vm/kernel_to_il.cc
+++ b/runtime/vm/kernel_to_il.cc
@@ -6056,12 +6056,11 @@ void FlowGraphBuilder::VisitYieldStatement(YieldStatement* node) {
 
   Fragment continuation(instructions.entry, anchor);
 
-  // TODO(27590): we need a better way to detect if we need to check for an
-  // exception after yield or not.
-  if (parsed_function_->function().NumOptionalPositionalParameters() == 3) {
-    // If function takes three parameters then the second and the third
-    // are exception and stack_trace. Check if exception is non-null
-    // and rethrow it.
+  if (parsed_function_->function().IsAsyncClosure() ||
+      parsed_function_->function().IsAsyncGenClosure()) {
+    // If function is async closure or async gen closure it takes three
+    // parameters where the second and the third are exception and stack_trace.
+    // Check if exception is non-null and rethrow it.
     //
     //   :async_op([:result, :exception, :stack_trace]) {
     //     ...
@@ -6132,7 +6131,26 @@ Fragment FlowGraphBuilder::TranslateFunctionNode(FunctionNode* node,
       // NOTE: This is not TokenPosition in the general sense!
       function = Function::NewClosureFunction(
           *name, parsed_function_->function(), position);
-      function.set_is_debuggable(node->debuggable());
+
+      function.set_is_debuggable(node->dart_async_marker() ==
+                                 FunctionNode::kSync);
+      switch (node->dart_async_marker()) {
+        case FunctionNode::kSyncStar:
+          function.set_modifier(RawFunction::kSyncGen);
+          break;
+        case FunctionNode::kAsync:
+          function.set_modifier(RawFunction::kAsync);
+          break;
+        case FunctionNode::kAsyncStar:
+          function.set_modifier(RawFunction::kAsyncGen);
+          break;
+        default:
+          // no special modifier
+          break;
+      }
+      function.set_is_generated_body(node->async_marker() ==
+                                     FunctionNode::kSyncYielding);
+
       function.set_end_token_pos(node->end_position());
       LocalScope* scope = scopes_->function_scopes[i].scope;
       const ContextScope& context_scope =