Perform a microtask checkpoint for document.write('<script><\/script>')

Source/core/html/parser/HTMLScriptRunner.cpp

Index: Source/core/html/parser/HTMLScriptRunner.cpp
diff --git a/Source/core/html/parser/HTMLScriptRunner.cpp b/Source/core/html/parser/HTMLScriptRunner.cpp
index 871096253b10d046ba70f35ae60ed435ebeed42d..1efcad2a0241b1de84fd00c71227a54f12af545b 100644
--- a/Source/core/html/parser/HTMLScriptRunner.cpp
+++ b/Source/core/html/parser/HTMLScriptRunner.cpp
@@ -286,12 +286,7 @@ void HTMLScriptRunner::runScript(Element* script, const TextPosition& scriptStar
         if (!scriptLoader)
             return;
 
-        // FIXME: This may be too agressive as we always deliver mutations at
-        // every script element, even if it's not ready to execute yet. There's
-        // unfortuantely no obvious way to tell if prepareScript is going to
-        // execute the script from out here.
-        if (!isExecutingScript())
-            Microtask::performCheckpoint();
+        Microtask::performCheckpoint();

[esprehn, 2014/02/11 00:44:49]

This is not correct, now appendChild(script) does a micro task checkpoint right
then.

 
         InsertionPointRecord insertionPointRecord(m_host->inputStream());
         NestingLevelIncrementer nestingLevelIncrementer(m_scriptNestingLevel);