[debugger] handle stack overflow. Fail silently.

src/debug/debug-scopes.h

 // Copyright 2015 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_SCOPES_H_
 #define V8_DEBUG_DEBUG_SCOPES_H_
 
 #include "src/debug/debug-frames.h"
 #include "src/frames.h"
 
@@ skipping 32 matching lines @@
 
   ScopeIterator(Isolate* isolate, FrameInspector* frame_inspector,
                 Option options = DEFAULT);
 
   ScopeIterator(Isolate* isolate, Handle<JSFunction> function);
   ScopeIterator(Isolate* isolate, Handle<JSGeneratorObject> generator);
 
   MUST_USE_RESULT MaybeHandle<JSObject> MaterializeScopeDetails();
 
   // More scopes?
-  bool Done() {
-    DCHECK(!failed_);
-    return context_.is_null();
-  }
-
-  bool Failed() { return failed_; }
+  bool Done() { return context_.is_null(); }
 
   // Move to the next scope.
   void Next();
 
   // Return the type of the current scope.
   ScopeType Type();
 
   // Return the JavaScript object with the content of the current scope.
   MaybeHandle<JSObject> ScopeObject();
 
@@ skipping 27 matching lines @@
     int end_position;
     bool is_hidden() { return start_position == -1 && end_position == -1; }
   };
 
   Isolate* isolate_;
   FrameInspector* const frame_inspector_;
   Handle<Context> context_;
   List<ExtendedScopeInfo> nested_scope_chain_;
   Handle<StringSet> non_locals_;
   bool seen_script_scope_;
-  bool failed_;
 
   inline JavaScriptFrame* GetFrame() {
     return frame_inspector_->GetArgumentsFrame();
   }
 
   inline Handle<JSFunction> GetFunction() {
     return frame_inspector_->GetFunction();
   }
 
   void RetrieveScopeChain(DeclarationScope* scope);
@@ skipping 50 matching lines @@
   void GetNestedScopeChain(Isolate* isolate, Scope* scope,
                            int statement_position);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(ScopeIterator);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_DEBUG_DEBUG_SCOPES_H_