Reapply "Move isolate loading to a separate loader isolate."

Source/bindings/dart/DartDOMData.cpp

Index: Source/bindings/dart/DartDOMData.cpp
diff --git a/Source/bindings/dart/DartDOMData.cpp b/Source/bindings/dart/DartDOMData.cpp
index 16b852a1ac4b3655d4c1f58935b23415941fc746..338988e3e131ca7fed62fff15181365a2c83e878 100644
--- a/Source/bindings/dart/DartDOMData.cpp
+++ b/Source/bindings/dart/DartDOMData.cpp
@@ -32,6 +32,7 @@
 #include "bindings/dart/DartDOMData.h"
 
 #include "bindings/dart/DartApplicationLoader.h"
+#include "bindings/dart/DartAsyncLoader.h"
 #include "bindings/dart/ThreadSafeDartIsolateWrapper.h"
 #include "core/dom/ScriptExecutionContext.h"
 
@@ -86,6 +87,18 @@ PassRefPtr<DartApplicationLoader> DartDOMData::applicationLoader()
     return m_applicationLoader;
 }
 
+void DartDOMData::setAsyncLoader(PassRefPtr<DartAsyncLoader> asyncLoader)
+{
+    ASSERT(!m_asyncLoader || !asyncLoader);
+    m_asyncLoader = asyncLoader;
+}
+
+PassRefPtr<DartAsyncLoader> DartDOMData::asyncLoader()
+{
+    ASSERT(m_asyncLoader);
+    return m_asyncLoader;
+}
+
 void DartDOMData::setThreadSafeIsolateWrapper(PassRefPtr<ThreadSafeDartIsolateWrapper> threadSafeIsolateWrapper)
 {
     ASSERT(!m_threadSafeIsolateWrapper);