[debugger] simplify debug stepping.

src/arm/macro-assembler-arm.cc

Index: src/arm/macro-assembler-arm.cc
diff --git a/src/arm/macro-assembler-arm.cc b/src/arm/macro-assembler-arm.cc
index 2c06e1ea74ae0472f93b2b76f2fbee1745bf5593..db22eb07d55ab19f700a1ac63963c4c6fb34b47b 100644
--- a/src/arm/macro-assembler-arm.cc
+++ b/src/arm/macro-assembler-arm.cc
@@ -1579,12 +1579,13 @@ void MacroAssembler::FloodFunctionIfStepping(Register fun, Register new_target,
                                              const ParameterCount& expected,
                                              const ParameterCount& actual) {
   Label skip_flooding;
-  ExternalReference step_in_enabled =
-      ExternalReference::debug_step_in_enabled_address(isolate());
-  mov(r4, Operand(step_in_enabled));
-  ldrb(r4, MemOperand(r4));
-  cmp(r4, Operand(0));
-  b(eq, &skip_flooding);
+  ExternalReference last_step_action =
+      ExternalReference::debug_last_step_action_address(isolate());
+  STATIC_ASSERT(StepFrame > StepIn);
+  mov(r4, Operand(last_step_action));
+  ldrsb(r4, MemOperand(r4));
+  cmp(r4, Operand(StepIn));
+  b(lt, &skip_flooding);
   {
     FrameScope frame(this,
                      has_frame() ? StackFrame::NONE : StackFrame::INTERNAL);