[debugger] step-next across yield should not leave the generator.

src/runtime/runtime-generator.cc

 // Copyright 2014 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/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/debug/debug.h"
 #include "src/factory.h"
 #include "src/frames-inl.h"
@@ skipping 36 matching lines @@
   DCHECK(args.length() == 1);
   CONVERT_ARG_HANDLE_CHECKED(JSGeneratorObject, generator_object, 0);
 
   JavaScriptFrameIterator stack_iterator(isolate);
   JavaScriptFrame* frame = stack_iterator.frame();
   CHECK(IsResumableFunction(frame->function()->shared()->kind()));
   DCHECK_EQ(frame->function(), generator_object->function());
   DCHECK(frame->function()->shared()->is_compiled());
   DCHECK(!frame->function()->IsOptimized());
 
-  isolate->debug()->RecordAsyncFunction(generator_object);
+  isolate->debug()->RecordGenerator(generator_object);
 
   // The caller should have saved the context and continuation already.
   DCHECK_EQ(generator_object->context(), Context::cast(frame->context()));
   DCHECK_LT(0, generator_object->continuation());
 
   // We expect there to be at least two values on the operand stack: the return
   // value of the yield expression, and the arguments to this runtime call.
   // Neither of those should be saved.
   int operands_count = frame->ComputeOperandsCount();
   DCHECK_GE(operands_count, 1 + args.length());
@@ skipping 68 matching lines @@
   HandleScope scope(isolate);
   DCHECK(args.length() == 1);
   CONVERT_ARG_HANDLE_CHECKED(JSGeneratorObject, generator, 0);
 
   if (!generator->is_suspended()) return isolate->heap()->undefined_value();
   return Smi::FromInt(generator->source_position());
 }
 
 }  // namespace internal
 }  // namespace v8