Correctly keep track of isolates for microtask execution

Source/core/dom/Microtask.h

Index: Source/core/dom/Microtask.h
diff --git a/Source/core/dom/Microtask.h b/Source/core/dom/Microtask.h
index ceec178f852b0e271744747402cbd9f1fe1bff81..e2c86bbc226392a47d1d6caa2d793c23756a27b9 100644
--- a/Source/core/dom/Microtask.h
+++ b/Source/core/dom/Microtask.h
@@ -31,6 +31,7 @@
 #ifndef Microtask_h
 #define Microtask_h
 
+#include "bindings/core/v8/ScriptState.h"

[vivekg, 2015/05/27 14:59:37]

nit: Do we need to include ScriptState.h here?

 #include "core/CoreExport.h"
 #include "public/platform/WebThread.h"
 #include "wtf/Functional.h"
@@ -41,7 +42,7 @@ namespace blink {
 
 class CORE_EXPORT Microtask {
 public:
-    static void performCheckpoint();
+    static void performCheckpoint(v8::Isolate*);
     static bool performingCheckpoint(v8::Isolate*);
     static void enqueueMicrotask(PassOwnPtr<WebThread::Task>);
     static void enqueueMicrotask(PassOwnPtr<Closure>);