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diff --git a/chromium/third_party/blink/renderer/core/execution_context/execution_context_lifecycle_observer.h b/chromium/third_party/blink/renderer/core/execution_context/execution_context_lifecycle_observer.h
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+/*
+ * Copyright (C) 2008 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_EXECUTION_CONTEXT_EXECUTION_CONTEXT_LIFECYCLE_OBSERVER_H_
+#define THIRD_PARTY_BLINK_RENDERER_CORE_EXECUTION_CONTEXT_EXECUTION_CONTEXT_LIFECYCLE_OBSERVER_H_
+
+#include "third_party/blink/renderer/core/core_export.h"
+#include "third_party/blink/renderer/platform/context_lifecycle_observer.h"
+
+namespace blink {
+
+class ExecutionContext;
+class Document;
+class LocalDOMWindow;
+class LocalFrame;
+
+// ExecutionContextClient and ExecutionContextLifecycleObserver are helpers to
+// associate an object with an ExecutionContext. It is unsafe to access an
+// associated GC object, *including via GetExecutionContext()*, in the
+// destructor of a GC object.
+//
+// To discourage incorrect usage, these objects both start returning null
+// once the execution context shuts down. For a document, this occurs when
+// the frame navigates to another document or is detached. For a worker global
+// scope, this occurs when it shuts down.
+//
+// * If an object only needs to refer to a valid ExecutionContext but does not
+//   need to stop or suspend any activity, it should be a
+//   ExecutionContextClient.
+// * If an object associated with an ExecutionContext has shutdown logic to
+//   perform, such as halting activity or disconnecting from longer-lived
+//   objects, it should be a PausableObject.
+// * If an object additionally must suspend its activity during pause (see
+//   execution_context_lifecycle_state_observer.h), it should be a
+//   ExecutionContextLifecycleStateObserver (and thus, transitively, also a
+//   ExecutionContextLifecycleObserver).
+//
+// If your object has activity which requires that it be kept alive, even if no
+// other object has a reference to it, consider whether your object should also
+// derive from ActiveScriptWrappable.
+
+// ExecutionContextClient provides access to the associated execution context
+// until it is shut down (e.g. for a document, at navigation or frame detach).
+class CORE_EXPORT ExecutionContextClient : public GarbageCollectedMixin {
+ public:
+  // Returns the execution context until it is detached.
+  // From then on, returns null instead.
+  ExecutionContext* GetExecutionContext() const;
+
+  // Return a live document if associated with it. Returns null otherwise.
+  Document* GetDocument() const;
+
+  // If associated with a live document, returns the associated frame.
+  // Returns null otherwise.
+  LocalFrame* GetFrame() const;
+
+  void Trace(Visitor*) override;
+
+ protected:
+  explicit ExecutionContextClient(ExecutionContext*);
+  explicit ExecutionContextClient(LocalFrame*);
+
+ private:
+  WeakMember<ExecutionContext> execution_context_;
+};
+
+// ExecutionContextLifecycleObserver provides an additional ContextDestroyed()
+// hook to execute cleanup code when a context is shut down (e.g. for a
+// document, at navigation or frame detach -- not when its destructor runs).
+//
+// Execution context associated objects which have ongoing activity,
+// registration with objects which outlive the context, or resources which
+// should be promptly released, should consider deriving from
+// PausableObject. As a rule of thumb: if the destructor contains
+// non-trivial logic, that logic may belong in ContextDestroyed() instead.
+//
+// If there is ongoing activity associated with the object, consider whether it
+// needs to be paused when execution is suspended (see
+// ExecutionContextLifecycleStateObserver).
+//
+// If none of the above applies, prefer the simpler ExecutionContextClient.
+class CORE_EXPORT ExecutionContextLifecycleObserver
+    : public ContextLifecycleObserver {
+ public:
+
+  // Returns the execution context until it is detached.
+  // From then on, returns null instead.
+  ExecutionContext* GetExecutionContext() const;
+  virtual void SetExecutionContext(ExecutionContext*);
+
+  // If associated with a live document, returns the associated frame.
+  // Returns null otherwise.
+  LocalFrame* GetFrame() const;
+
+  enum Type {
+    kGenericType,
+    kStateObjectType,
+  };
+
+  Type ObserverType() const { return observer_type_; }
+
+  bool IsExecutionContextLifecycleObserver() const override { return true; }
+
+  void Trace(Visitor*) override;
+
+ protected:
+  ExecutionContextLifecycleObserver();
+  // TODO(crbug.com/1029822): This is a shim to enable migrating
+  // ExecutionContext to LocalDOMWindow.
+  explicit ExecutionContextLifecycleObserver(Document*,
+                                             Type type = kGenericType);
+
+  explicit ExecutionContextLifecycleObserver(
+      ExecutionContext* execution_context,
+      Type type = kGenericType);
+
+ private:
+  Type observer_type_;
+};
+
+// DOMWindowClient is a helper to associate an object with a LocalDOMWindow.
+//
+// - domWindow() returns null after the window is detached.
+// - frame() is a syntax sugar for domWindow()->frame(). It returns
+//   null after the window is detached.
+//
+// Both can safely be used up until destruction; i.e., unsafe to
+// call upon in a destructor.
+//
+// If the object is a per-ExecutionContext thing, use ExecutionContextClient/
+// ExecutionContextLifecycleObserver. If the object is a per-DOMWindow thing,
+// use DOMWindowClient. Basically, DOMWindowClient is expected to be used (only)
+// for objects directly held by LocalDOMWindow. Other objects should use
+// ExecutionContextClient/ExecutionContextLifecycleObserver.
+//
+// There is a subtle difference between the timing when the context gets
+// detached and the timing when the window gets detached. In common cases,
+// these two happen at the same timing. The only exception is a case where
+// a frame navigates from an initial empty document to another same-origin
+// document. In this case, a Document is recreated but a DOMWindow is reused.
+// Hence, in the navigated document
+// ExecutionContextClient::GetExecutionContext() returns null while
+// DOMWindowClient::domWindow() keeps returning the window.
+class CORE_EXPORT DOMWindowClient : public GarbageCollectedMixin {
+ public:
+  LocalDOMWindow* DomWindow() const;
+  LocalFrame* GetFrame() const;
+
+  void Trace(Visitor*) override;
+
+ protected:
+  explicit DOMWindowClient(LocalDOMWindow*);
+  explicit DOMWindowClient(LocalFrame*);
+
+ private:
+  WeakMember<LocalDOMWindow> dom_window_;
+};
+
+}  // namespace blink
+
+#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_EXECUTION_CONTEXT_EXECUTION_CONTEXT_LIFECYCLE_OBSERVER_H_