LiveEdit: implement frame dropping

src/liveedit.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 73 matching lines @@
 
   static void ReplaceFunctionCode(Handle<JSArray> new_compile_info_array,
                                   Handle<JSArray> shared_info_array);
 
   static void RelinkFunctionToScript(Handle<JSArray> shared_info_array,
                                      Handle<Script> script_handle);
 
   static void PatchFunctionPositions(Handle<JSArray> shared_info_array,
                                      Handle<JSArray> position_change_array);
 
+  // Checks listed functions on stack and return array with corresponding
+  // FunctionPatchabilityStatus statuses; extra array element may
+  // contain general error message. Modifies the current stack and
+  // has restart the lowest found frames and drops all other frames above
+  // if possible and if do_drop is true.
+  static Handle<JSArray> CheckAndDropActivations(
+      Handle<JSArray> shared_info_array, bool do_drop);
+
   // A copy of this is in liveedit-debugger.js.
   enum FunctionPatchabilityStatus {
-    FUNCTION_AVAILABLE_FOR_PATCH = 0,
-    FUNCTION_BLOCKED_ON_STACK = 1
+    FUNCTION_AVAILABLE_FOR_PATCH = 1,
+    FUNCTION_BLOCKED_ON_ACTIVE_STACK = 2,
+    FUNCTION_BLOCKED_ON_OTHER_STACK = 3,
+    FUNCTION_BLOCKED_UNDER_NATIVE_CODE = 4,
+    FUNCTION_REPLACED_ON_ACTIVE_STACK = 5
   };
 };
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 
 } }  // namespace v8::internal
 
 #endif /* V*_LIVEEDIT_H_ */