[debugger] fix stepping over await calls for ignition generators.

src/interpreter/interpreter-assembler.cc

Index: src/interpreter/interpreter-assembler.cc
diff --git a/src/interpreter/interpreter-assembler.cc b/src/interpreter/interpreter-assembler.cc
index d878c5c69370b4904e5963b81e6487f34d7a3ae7..10fb9635fd12b334bb196157495524d90a9fc8da 100644
--- a/src/interpreter/interpreter-assembler.cc
+++ b/src/interpreter/interpreter-assembler.cc
@@ -620,6 +620,12 @@ Node* InterpreterAssembler::StackCheckTriggeredInterrupt() {
   return UintPtrLessThan(sp, stack_limit);
 }
 
+Node* InterpreterAssembler::DebuggerIsActive() {
+  return Load(
+      MachineType::Pointer(),

[Benedikt Meurer, 2016/06/14 03:45:36]

This doesn't look quite right here. The is_active_ field is a bool, so we
probably need MachineType::Int8() here, although I'm not sure that C++ always
stores bool into int8. Maybe we can explicitly change the fields in debug.h to
int8_t to be sure?

[rmcilroy, 2016/06/14 06:23:11]

Yes, it's implementation defined. It's probably always a byte on compilers we
use, but I agree we should change the field to be sure.

[Yang, 2016/06/14 09:17:02]

I changed this. We now don't load is_active_ anymore, but last_step_action_
instead.

+      ExternalConstant(ExternalReference::debug_is_active_address(isolate())));
+}
+
 void InterpreterAssembler::Abort(BailoutReason bailout_reason) {
   disable_stack_check_across_call_ = true;
   Node* abort_id = SmiTag(Int32Constant(bailout_reason));