Extract tree root responsibility out of HTMLImportsController.

Source/core/html/imports/HTMLImportTreeRoot.cpp

Index: Source/core/html/imports/HTMLImportTreeRoot.cpp
diff --git a/Source/core/html/imports/HTMLImportTreeRoot.cpp b/Source/core/html/imports/HTMLImportTreeRoot.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..d44d93291be97f173f54b87f1c95423d30bae3a6
--- /dev/null
+++ b/Source/core/html/imports/HTMLImportTreeRoot.cpp
@@ -0,0 +1,69 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+#include "core/html/imports/HTMLImportTreeRoot.h"
+
+#include "core/dom/Document.h"
+#include "core/dom/StyleEngine.h"
+#include "core/frame/LocalFrame.h"
+
+namespace WebCore {
+
+PassOwnPtr<HTMLImportTreeRoot> HTMLImportTreeRoot::create(Document* document)
+{
+    return adoptPtr(new HTMLImportTreeRoot(document));
+}
+
+HTMLImportTreeRoot::HTMLImportTreeRoot(Document* document)
+    : HTMLImport(HTMLImport::Sync)
+    , m_document(document)
+    , m_recalcTimer(this, &HTMLImportTreeRoot::recalcTimerFired)
+{
+    recalcTreeState(this); // This recomputes initial state.
+}
+
+Document* HTMLImportTreeRoot::document() const
+{
+    return m_document;
+}
+
+bool HTMLImportTreeRoot::isDone() const
+{
+    return !m_document->parsing() && m_document->styleEngine()->haveStylesheetsLoaded();
+}
+
+void HTMLImportTreeRoot::stateWillChange()
+{
+    scheduleRecalcState();
+}
+
+void HTMLImportTreeRoot::stateDidChange()
+{
+    HTMLImport::stateDidChange();
+
+    if (!state().isReady())
+        return;
+    if (LocalFrame* frame = m_document->frame())
+        frame->loader().checkCompleted();
+}
+
+void HTMLImportTreeRoot::scheduleRecalcState()
+{
+    if (m_recalcTimer.isActive() || !m_document)
+        return;
+    m_recalcTimer.startOneShot(0, FROM_HERE);
+}
+
+void HTMLImportTreeRoot::recalcTimerFired(Timer<HTMLImportTreeRoot>*)
+{
+    ASSERT(m_document);
+
+    do {
+        m_recalcTimer.stop();
+        HTMLImport::recalcTreeState(this);
+    } while (m_recalcTimer.isActive());
+}
+
+}