WIP: Entry realm stack in Blink

third_party/WebKit/Source/bindings/core/v8/V8PerIsolateData.h

Index: third_party/WebKit/Source/bindings/core/v8/V8PerIsolateData.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/V8PerIsolateData.h b/third_party/WebKit/Source/bindings/core/v8/V8PerIsolateData.h
index 17d08c74f148512e7c4658abccb6ca99c46c430f..26674080b389c6d0e43a31e6db0e78792016fecd 100644
--- a/third_party/WebKit/Source/bindings/core/v8/V8PerIsolateData.h
+++ b/third_party/WebKit/Source/bindings/core/v8/V8PerIsolateData.h
@@ -90,6 +90,25 @@ class CORE_EXPORT V8PerIsolateData {
     const bool m_originalUseCounterDisabled;
   };
 
+  class EntryRealmScope {
+    STACK_ALLOCATED();
+
+   public:
+    explicit EntryRealmScope(V8PerIsolateData* perIsolateData,
+                             v8::Local<v8::Context> entryContext)
+        : m_perIsolateData(perIsolateData),
+          m_previousEntryContext(m_perIsolateData->m_entryContext) {
+      m_perIsolateData->m_entryContext = entryContext;
+    }
+    ~EntryRealmScope() {
+      m_perIsolateData->m_entryContext = m_previousEntryContext;
+    }
+
+   private:
+    V8PerIsolateData* m_perIsolateData;
+    v8::Local<v8::Context> m_previousEntryContext;
+  };
+
   // Use this class to abstract away types of members that are pointers to core/
   // objects, which are simply owned and released by V8PerIsolateData (see
   // m_threadDebugger for an example).
@@ -132,6 +151,13 @@ class CORE_EXPORT V8PerIsolateData {
 
   bool isUseCounterDisabled() const { return m_useCounterDisabled; }
 
+  v8::Local<v8::Context> entryContext() {
+    DCHECK(!m_entryContext.IsEmpty());
+    if (m_entryContext.IsEmpty())
+      return isolate()->GetEnteredContext();
+    return m_entryContext;
+  }
+
   V8HiddenValue* hiddenValue() { return m_hiddenValue.get(); }
   V8PrivateProperty* privateProperty() { return m_privateProperty.get(); }
 
@@ -250,6 +276,9 @@ class CORE_EXPORT V8PerIsolateData {
   bool m_useCounterDisabled;
   friend class UseCounterDisabledScope;
 
+  v8::Local<v8::Context> m_entryContext;
+  friend class EntryRealmScope;
+
   bool m_isHandlingRecursionLevelError;
   bool m_isReportingException;