Disables MinorGC from collecting object wrappers

third_party/WebKit/Source/bindings/core/v8/V8GCController.cpp

 /*
  * Copyright (C) 2009 Google Inc. 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
@@ skipping 125 matching lines @@
                 v8::Persistent<v8::Object>::Cast(*value).MarkActive();
                 return;
             }
             // FIXME: Remove the special handling for SVG elements.
             // We currently can't collect SVG Elements from minor gc, as we have
             // strong references from SVG property tear-offs keeping context SVG element alive.
             if (node->isSVGElement()) {
                 v8::Persistent<v8::Object>::Cast(*value).MarkActive();
                 return;
             }
+        }  else {
+            // If there are any references to this object mark it as active.
+            // Current MinorGC pass does not handle references.
+            if (type->visitDOMWrapperFunction) {

[haraken, 2015/11/24 12:59:08]

Unfortunately this check is not correct. type->visitDOMWrapperFunction means
that this wrapper has a reference to some wrapper, not that this object is
referenced by some wrapper.

[mythria, 2015/11/24 14:21:44]

Thank you for your review. Reverted this change. 

+                v8::Persistent<v8::Object>::Cast(*value).MarkActive();

[mythria, 2015/11/24 11:50:19]

Would this check be sufficient to filter out all object wrappers that could
contain a reference? If it is not then I will revert it back to the earlier
code, where we ignore all object wrappers in minor GC.

+                return;
+            }
         }
     }
 
 private:
     v8::Isolate* m_isolate;
 };
 
 class MajorGCWrapperVisitor : public v8::PersistentHandleVisitor {
 public:
     explicit MajorGCWrapperVisitor(v8::Isolate* isolate, bool constructRetainedObjectInfos)
@@ skipping 283 matching lines @@
     Visitor* m_visitor;
 };
 
 void V8GCController::traceDOMWrappers(v8::Isolate* isolate, Visitor* visitor)
 {
     DOMWrapperTracer tracer(visitor);
     v8::V8::VisitHandlesWithClassIds(isolate, &tracer);
 }
 
 } // namespace blink