Defer late and async scripts

Source/core/dom/ScriptLoader.cpp

Index: Source/core/dom/ScriptLoader.cpp
diff --git a/Source/core/dom/ScriptLoader.cpp b/Source/core/dom/ScriptLoader.cpp
index f69e0e63d362e4750b5f16bbce060813de6b7058..4dea7b47e475275550b62de50658a5a59fdaef79 100644
--- a/Source/core/dom/ScriptLoader.cpp
+++ b/Source/core/dom/ScriptLoader.cpp
@@ -65,6 +65,8 @@ ScriptLoader::ScriptLoader(Element* element, bool parserInserted, bool alreadySt
     , m_readyToBeParserExecuted(false)
     , m_willExecuteWhenDocumentFinishedParsing(false)
     , m_forceAsync(!parserInserted)
+    , m_hasAsyncAttribute(false)
+    , m_hasDeferAttribute(false)
     , m_willExecuteInOrder(false)
 {
     ASSERT(m_element);
@@ -100,6 +102,7 @@ void ScriptLoader::handleSourceAttribute(const String& sourceUrl)
 void ScriptLoader::handleAsyncAttribute()
 {
     m_forceAsync = false;
+    m_hasAsyncAttribute = true;
 }
 
 // Helper function
@@ -184,6 +187,9 @@ bool ScriptLoader::prepareScript(const TextPosition& scriptStartPosition, Legacy
     if (wasParserInserted && !client->asyncAttributeValue())
         m_forceAsync = true;
 
+    if (client->deferAttributeValue())
+        m_hasDeferAttribute = true;
+
     // FIXME: HTML5 spec says we should check that all children are either comments or empty text nodes.
     if (!client->hasSourceAttribute() && !m_element->hasChildren())
         return false;
@@ -267,6 +273,9 @@ bool ScriptLoader::fetchScript(const String& sourceUrl)
         if (scriptPassesCSP)
             request.setContentSecurityCheck(DoNotCheckContentSecurityPolicy);
 
+        if (!m_parserInserted || m_hasAsyncAttribute || m_hasDeferAttribute)
+            request.setExecAsync(true);
+
         m_resource = elementDocument->fetcher()->fetchScript(request);
         m_isExternalScript = true;
     }