Support merged Dart-JS callstacks

Source/bindings/v8/V8RecursionScope.h

Index: Source/bindings/v8/V8RecursionScope.h
diff --git a/Source/bindings/v8/V8RecursionScope.h b/Source/bindings/v8/V8RecursionScope.h
index 0a150c3b9fe6a96058f3519a0f6bcd5e2ea726aa..962375bec61189dabe8a993efc358400ec474f8c 100644
--- a/Source/bindings/v8/V8RecursionScope.h
+++ b/Source/bindings/v8/V8RecursionScope.h
@@ -31,6 +31,7 @@
 #ifndef V8RecursionScope_h
 #define V8RecursionScope_h
 
+#include "bindings/common/StackTrace.h"
 #include "bindings/v8/V8PerIsolateData.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/dom/ScriptForbiddenScope.h"
@@ -59,11 +60,16 @@ namespace WebCore {
 class V8RecursionScope {
     WTF_MAKE_NONCOPYABLE(V8RecursionScope);
 public:
-    V8RecursionScope(v8::Isolate* isolate, ExecutionContext* context)
+    V8RecursionScope(v8::Isolate* isolate, ExecutionContext* context, bool shouldTrackStackDepth = true)
         : m_isolate(isolate)
         , m_executionContext(context)
+        , m_shouldTrackStackDepth(shouldTrackStackDepth)
     {
-        V8PerIsolateData::from(m_isolate)->incrementRecursionLevel();
+        V8PerIsolateData* isolateData = V8PerIsolateData::from(m_isolate);
+
+        if (shouldTrackStackDepth)
+            trackStackDepth(isolateData);
+        isolateData->incrementRecursionLevel();
         ASSERT(!ScriptForbiddenScope::isScriptForbidden());
         // If you want V8 to autorun microtasks, this class needs to have a
         // v8::Isolate::SuppressMicrotaskExecutionScope member.
@@ -72,7 +78,10 @@ public:
 
     ~V8RecursionScope()
     {
-        if (!V8PerIsolateData::from(m_isolate)->decrementRecursionLevel())
+        V8PerIsolateData* isolateData = V8PerIsolateData::from(m_isolate);
+        if (m_shouldTrackStackDepth)
+            isolateData->stackTraceTimestampTracker()->decrementRecursionLevel();
+        if (isolateData->decrementRecursionLevel())
             didLeaveScriptContext();
     }
 
@@ -116,11 +125,13 @@ public:
 
 private:
     void didLeaveScriptContext();
+    void trackStackDepth(V8PerIsolateData*);
 
     v8::Isolate* m_isolate;
     // FIXME: This is a reference in upstream Blink. In Dartium, it can
     // be null when instantiated from a DartUtilities::V8Scope.
     ExecutionContext* m_executionContext;
+    bool m_shouldTrackStackDepth;
 };
 
 } // namespace WebCore