[inspector] migrate stepping related methods to debug-interface

src/debug/debug.h

 // Copyright 2012 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.
 
 #ifndef V8_DEBUG_DEBUG_H_
 #define V8_DEBUG_DEBUG_H_
 
 #include "src/allocation.h"
 #include "src/arguments.h"
 #include "src/assembler.h"
@@ skipping 483 matching lines @@
                              LiveEditFrameDropMode mode);
 
   // Threading support.
   char* ArchiveDebug(char* to);
   char* RestoreDebug(char* from);
   static int ArchiveSpacePerThread();
   void FreeThreadResources() { }
   void Iterate(ObjectVisitor* v);
 
   bool CheckExecutionState(int id) {
-    return is_active() && !debug_context().is_null() && break_id() != 0 &&
-           break_id() == id;
+    return CheckExecutionState() && break_id() == id;
+  }
+
+  bool CheckExecutionState() {
+    return is_active() && !debug_context().is_null() && break_id() != 0;
   }
 
   // Flags and states.
   DebugScope* debugger_entry() {
     return reinterpret_cast<DebugScope*>(
         base::NoBarrier_Load(&thread_local_.current_debug_scope_));
   }
   inline Handle<Context> debug_context() { return debug_context_; }
 
   void set_live_edit_enabled(bool v) { live_edit_enabled_ = v; }
@@ skipping 305 matching lines @@
                                   Handle<Code> code);
   static bool DebugBreakSlotIsPatched(Address pc);
   static void ClearDebugBreakSlot(Isolate* isolate, Address pc);
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_DEBUG_DEBUG_H_