[HTML Imports] Make import loading in order.

Source/core/html/HTMLImport.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:
  *
  *     * 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 17 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/html/HTMLImport.h"
 
 #include "core/html/HTMLImportsController.h"
 
 namespace WebCore {
 
-bool HTMLImport::haveChildrenLoaded()
-{
-    if (HTMLImportsController* controller = this->controller())
-        return controller->haveChildrenLoaded(this);
-    return true;
-}
-
 Frame* HTMLImport::frame()
 {
     return master()->frame();
 }
 
 Document* HTMLImport::master()
 {
     return controller()->document();
 }
 
+void HTMLImport::appendChild(HTMLImport* child)
+{
+    ASSERT(child->parent() == this);
+    ASSERT(!child->hasChildren());
+
+    if (isBlocked())
+        child->setBlocked(true);
+    m_children.append(child);
+    blockAfter(child);
+}
+
+void HTMLImport::didUnblock()
+{
+    ASSERT(!isBlocked());
+    if (!isProcessing())
+        return;
+
+    if (Document* document = this->document())
+        document->didLoadAllImports();
+}
+
+bool HTMLImport::areChilrenLoaded() const
+{
+    for (size_t i = 0; i < m_children.size(); ++i) {
+        if (!m_children[i]->isLoaded())
+            return false;
+    }
+
+    return true;
+}
+
+bool HTMLImport::arePredecessorsLoaded() const
+{
+    HTMLImport* parent = this->parent();
+    if (!parent)
+        return true;
+
+    for (size_t i = 0; i < parent->m_children.size(); ++i) {
+        HTMLImport* sibling = parent->m_children[i];
+        if (sibling == this)
+            break;
+        if (!sibling->isLoaded())
+            return false;
+    }
+
+    return true;
+}
+
+bool HTMLImport::unblock(HTMLImport* import)
+{
+    ASSERT(import->arePredecessorsLoaded());
+    ASSERT(import->isBlocked() || import->areChilrenLoaded());
+
+    if (import->isBlocked()) {
+        for (size_t i = 0; i < import->m_children.size(); ++i) {
+            if (!unblock(import->m_children[i]))
+                return false;
+        }
+    }
+
+    import->setBlocked(false);

[dglazkov, 2013/07/30 22:45:27]

Sounds like this gets marked as unblocked even if import hasn't loaded?

[Hajime Morrita, 2013/07/31 00:49:40]

Yes! Unblocked means it can continue parsing. 
"loaded" is unblocked + parsed.
See HTMLImport::isLoaded().

+    import->didUnblock();

[dglazkov, 2013/07/30 22:45:27]

Will this cause multiple document->didLoadAllImports calls?

[Hajime Morrita, 2013/07/31 00:49:40]

Yes, I don't think that's a big deal though
because didLoadAllImports() is kinda idempotent.

Let me try to do "if isBlocked() didUnblock()" for clarification.

+    return import->isLoaded();
+}
+
+void HTMLImport::setTreeBlocked(bool blocked)
+{
+    setBlocked(blocked);
+    for (size_t i = 0; i < m_children.size(); ++i)
+        m_children[i]->setTreeBlocked(blocked);
+}
+
+void HTMLImport::blockAfter(HTMLImport* child)
+{
+    ASSERT(child->parent() == this);
+
+    for (size_t i = 0; i < m_children.size(); ++i) {
+        HTMLImport* sibling = m_children[m_children.size() - i - 1];
+        if (sibling == child)
+            break;
+        sibling->setTreeBlocked(true);
+    }
+
+    setBlocked(true);
+
+    if (HTMLImport* parent = this->parent())
+        parent->blockAfter(this);
+}
+
+
 } // namespace WebCore