HTML Imports: Fix race conditions on HTMLImportsChild

Source/core/dom/custom/CustomElementMicrotaskQueue.cpp

 /*
  * Copyright (C) 2013 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:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 85 matching lines @@
             break;
     }
 
     for (++i; i < m_queue.size(); ++i)
         remaining.append(m_queue[i].release());
     m_queue.swap(remaining);
 
     return accumulatedResult;
 }
 
+bool CustomElementMicrotaskQueue::needsProcessOrStop() const

[dominicc (has gone to gerrit), 2014/05/12 00:42:18]

I think the complexity of Imports has degraded this a bit... I think you should
try moving this back to imports (it resembles a lot of Imports code and is only
triggered by imports) and slay the complexity dragon there.

+{
+    for (size_t i = 0; i < m_queue.size(); ++i) {
+        if (m_queue[i]->needsProcessOrStop())
+            return true;
+    }
+
+    return false;
+}
+
 #if !defined(NDEBUG)
 void CustomElementMicrotaskQueue::show(unsigned indent)
 {
     for (unsigned q = 0; q < m_queue.size(); ++q) {
         if (m_queue[q])
             m_queue[q]->show(indent);
         else
             fprintf(stderr, "%*snull\n", indent, "");
     }
 }
 #endif
 
 } // namespace WebCore