LiveEdit: implement frame dropping

src/liveedit.h

Index: src/liveedit.h
diff --git a/src/liveedit.h b/src/liveedit.h
index 2a9cc628a1760405bbe950220388e1fab3c9e356..bd4c1ee85a3f09139b7d3e8917baaea1ea35f94e 100644
--- a/src/liveedit.h
+++ b/src/liveedit.h
@@ -91,10 +91,21 @@ class LiveEdit : AllStatic {
   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
   };
 };