Add m-esr52 at 52.6.0

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diff --git a/security/sandbox/chromium/base/callback.h b/security/sandbox/chromium/base/callback.h
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+++ b/security/sandbox/chromium/base/callback.h
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+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_CALLBACK_H_
+#define BASE_CALLBACK_H_
+
+#include "base/callback_forward.h"
+#include "base/callback_internal.h"
+#include "base/template_util.h"
+
+// NOTE: Header files that do not require the full definition of Callback or
+// Closure should #include "base/callback_forward.h" instead of this file.
+
+// -----------------------------------------------------------------------------
+// Introduction
+// -----------------------------------------------------------------------------
+//
+// The templated Callback class is a generalized function object. Together
+// with the Bind() function in bind.h, they provide a type-safe method for
+// performing partial application of functions.
+//
+// Partial application (or "currying") is the process of binding a subset of
+// a function's arguments to produce another function that takes fewer
+// arguments. This can be used to pass around a unit of delayed execution,
+// much like lexical closures are used in other languages. For example, it
+// is used in Chromium code to schedule tasks on different MessageLoops.
+//
+// A callback with no unbound input parameters (base::Callback<void()>)
+// is called a base::Closure. Note that this is NOT the same as what other
+// languages refer to as a closure -- it does not retain a reference to its
+// enclosing environment.
+//
+// MEMORY MANAGEMENT AND PASSING
+//
+// The Callback objects themselves should be passed by const-reference, and
+// stored by copy. They internally store their state via a refcounted class
+// and thus do not need to be deleted.
+//
+// The reason to pass via a const-reference is to avoid unnecessary
+// AddRef/Release pairs to the internal state.
+//
+//
+// -----------------------------------------------------------------------------
+// Quick reference for basic stuff
+// -----------------------------------------------------------------------------
+//
+// BINDING A BARE FUNCTION
+//
+//   int Return5() { return 5; }
+//   base::Callback<int()> func_cb = base::Bind(&Return5);
+//   LOG(INFO) << func_cb.Run();  // Prints 5.
+//
+// BINDING A CLASS METHOD
+//
+//   The first argument to bind is the member function to call, the second is
+//   the object on which to call it.
+//
+//   class Ref : public base::RefCountedThreadSafe<Ref> {
+//    public:
+//     int Foo() { return 3; }
+//     void PrintBye() { LOG(INFO) << "bye."; }
+//   };
+//   scoped_refptr<Ref> ref = new Ref();
+//   base::Callback<void()> ref_cb = base::Bind(&Ref::Foo, ref);
+//   LOG(INFO) << ref_cb.Run();  // Prints out 3.
+//
+//   By default the object must support RefCounted or you will get a compiler
+//   error. If you're passing between threads, be sure it's
+//   RefCountedThreadSafe! See "Advanced binding of member functions" below if
+//   you don't want to use reference counting.
+//
+// RUNNING A CALLBACK
+//
+//   Callbacks can be run with their "Run" method, which has the same
+//   signature as the template argument to the callback.
+//
+//   void DoSomething(const base::Callback<void(int, std::string)>& callback) {
+//     callback.Run(5, "hello");
+//   }
+//
+//   Callbacks can be run more than once (they don't get deleted or marked when
+//   run). However, this precludes using base::Passed (see below).
+//
+//   void DoSomething(const base::Callback<double(double)>& callback) {
+//     double myresult = callback.Run(3.14159);
+//     myresult += callback.Run(2.71828);
+//   }
+//
+// PASSING UNBOUND INPUT PARAMETERS
+//
+//   Unbound parameters are specified at the time a callback is Run(). They are
+//   specified in the Callback template type:
+//
+//   void MyFunc(int i, const std::string& str) {}
+//   base::Callback<void(int, const std::string&)> cb = base::Bind(&MyFunc);
+//   cb.Run(23, "hello, world");
+//
+// PASSING BOUND INPUT PARAMETERS
+//
+//   Bound parameters are specified when you create thee callback as arguments
+//   to Bind(). They will be passed to the function and the Run()ner of the
+//   callback doesn't see those values or even know that the function it's
+//   calling.
+//
+//   void MyFunc(int i, const std::string& str) {}
+//   base::Callback<void()> cb = base::Bind(&MyFunc, 23, "hello world");
+//   cb.Run();
+//
+//   A callback with no unbound input parameters (base::Callback<void()>)
+//   is called a base::Closure. So we could have also written:
+//
+//   base::Closure cb = base::Bind(&MyFunc, 23, "hello world");
+//
+//   When calling member functions, bound parameters just go after the object
+//   pointer.
+//
+//   base::Closure cb = base::Bind(&MyClass::MyFunc, this, 23, "hello world");
+//
+// PARTIAL BINDING OF PARAMETERS
+//
+//   You can specify some parameters when you create the callback, and specify
+//   the rest when you execute the callback.
+//
+//   void MyFunc(int i, const std::string& str) {}
+//   base::Callback<void(const std::string&)> cb = base::Bind(&MyFunc, 23);
+//   cb.Run("hello world");
+//
+//   When calling a function bound parameters are first, followed by unbound
+//   parameters.
+//
+//
+// -----------------------------------------------------------------------------
+// Quick reference for advanced binding
+// -----------------------------------------------------------------------------
+//
+// BINDING A CLASS METHOD WITH WEAK POINTERS
+//
+//   base::Bind(&MyClass::Foo, GetWeakPtr());
+//
+//   The callback will not be run if the object has already been destroyed.
+//   DANGER: weak pointers are not threadsafe, so don't use this
+//   when passing between threads!
+//
+// BINDING A CLASS METHOD WITH MANUAL LIFETIME MANAGEMENT
+//
+//   base::Bind(&MyClass::Foo, base::Unretained(this));
+//
+//   This disables all lifetime management on the object. You're responsible
+//   for making sure the object is alive at the time of the call. You break it,
+//   you own it!
+//
+// BINDING A CLASS METHOD AND HAVING THE CALLBACK OWN THE CLASS
+//
+//   MyClass* myclass = new MyClass;
+//   base::Bind(&MyClass::Foo, base::Owned(myclass));
+//
+//   The object will be deleted when the callback is destroyed, even if it's
+//   not run (like if you post a task during shutdown). Potentially useful for
+//   "fire and forget" cases.
+//
+// IGNORING RETURN VALUES
+//
+//   Sometimes you want to call a function that returns a value in a callback
+//   that doesn't expect a return value.
+//
+//   int DoSomething(int arg) { cout << arg << endl; }
+//   base::Callback<void(int)> cb =
+//       base::Bind(base::IgnoreResult(&DoSomething));
+//
+//
+// -----------------------------------------------------------------------------
+// Quick reference for binding parameters to Bind()
+// -----------------------------------------------------------------------------
+//
+// Bound parameters are specified as arguments to Bind() and are passed to the
+// function. A callback with no parameters or no unbound parameters is called a
+// Closure (base::Callback<void()> and base::Closure are the same thing).
+//
+// PASSING PARAMETERS OWNED BY THE CALLBACK
+//
+//   void Foo(int* arg) { cout << *arg << endl; }
+//   int* pn = new int(1);
+//   base::Closure foo_callback = base::Bind(&foo, base::Owned(pn));
+//
+//   The parameter will be deleted when the callback is destroyed, even if it's
+//   not run (like if you post a task during shutdown).
+//
+// PASSING PARAMETERS AS A scoped_ptr
+//
+//   void TakesOwnership(scoped_ptr<Foo> arg) {}
+//   scoped_ptr<Foo> f(new Foo);
+//   // f becomes null during the following call.
+//   base::Closure cb = base::Bind(&TakesOwnership, base::Passed(&f));
+//
+//   Ownership of the parameter will be with the callback until the it is run,
+//   when ownership is passed to the callback function. This means the callback
+//   can only be run once. If the callback is never run, it will delete the
+//   object when it's destroyed.
+//
+// PASSING PARAMETERS AS A scoped_refptr
+//
+//   void TakesOneRef(scoped_refptr<Foo> arg) {}
+//   scoped_refptr<Foo> f(new Foo)
+//   base::Closure cb = base::Bind(&TakesOneRef, f);
+//
+//   This should "just work." The closure will take a reference as long as it
+//   is alive, and another reference will be taken for the called function.
+//
+// PASSING PARAMETERS BY REFERENCE
+//
+//   Const references are *copied* unless ConstRef is used. Example:
+//
+//   void foo(const int& arg) { printf("%d %p\n", arg, &arg); }
+//   int n = 1;
+//   base::Closure has_copy = base::Bind(&foo, n);
+//   base::Closure has_ref = base::Bind(&foo, base::ConstRef(n));
+//   n = 2;
+//   foo(n);                        // Prints "2 0xaaaaaaaaaaaa"
+//   has_copy.Run();                // Prints "1 0xbbbbbbbbbbbb"
+//   has_ref.Run();                 // Prints "2 0xaaaaaaaaaaaa"
+//
+//   Normally parameters are copied in the closure. DANGER: ConstRef stores a
+//   const reference instead, referencing the original parameter. This means
+//   that you must ensure the object outlives the callback!
+//
+//
+// -----------------------------------------------------------------------------
+// Implementation notes
+// -----------------------------------------------------------------------------
+//
+// WHERE IS THIS DESIGN FROM:
+//
+// The design Callback and Bind is heavily influenced by C++'s
+// tr1::function/tr1::bind, and by the "Google Callback" system used inside
+// Google.
+//
+//
+// HOW THE IMPLEMENTATION WORKS:
+//
+// There are three main components to the system:
+//   1) The Callback classes.
+//   2) The Bind() functions.
+//   3) The arguments wrappers (e.g., Unretained() and ConstRef()).
+//
+// The Callback classes represent a generic function pointer. Internally,
+// it stores a refcounted piece of state that represents the target function
+// and all its bound parameters.  Each Callback specialization has a templated
+// constructor that takes an BindState<>*.  In the context of the constructor,
+// the static type of this BindState<> pointer uniquely identifies the
+// function it is representing, all its bound parameters, and a Run() method
+// that is capable of invoking the target.
+//
+// Callback's constructor takes the BindState<>* that has the full static type
+// and erases the target function type as well as the types of the bound
+// parameters.  It does this by storing a pointer to the specific Run()
+// function, and upcasting the state of BindState<>* to a
+// BindStateBase*. This is safe as long as this BindStateBase pointer
+// is only used with the stored Run() pointer.
+//
+// To BindState<> objects are created inside the Bind() functions.
+// These functions, along with a set of internal templates, are responsible for
+//
+//  - Unwrapping the function signature into return type, and parameters
+//  - Determining the number of parameters that are bound
+//  - Creating the BindState storing the bound parameters
+//  - Performing compile-time asserts to avoid error-prone behavior
+//  - Returning an Callback<> with an arity matching the number of unbound
+//    parameters and that knows the correct refcounting semantics for the
+//    target object if we are binding a method.
+//
+// The Bind functions do the above using type-inference, and template
+// specializations.
+//
+// By default Bind() will store copies of all bound parameters, and attempt
+// to refcount a target object if the function being bound is a class method.
+// These copies are created even if the function takes parameters as const
+// references. (Binding to non-const references is forbidden, see bind.h.)
+//
+// To change this behavior, we introduce a set of argument wrappers
+// (e.g., Unretained(), and ConstRef()).  These are simple container templates
+// that are passed by value, and wrap a pointer to argument.  See the
+// file-level comment in base/bind_helpers.h for more info.
+//
+// These types are passed to the Unwrap() functions, and the MaybeRefcount()
+// functions respectively to modify the behavior of Bind().  The Unwrap()
+// and MaybeRefcount() functions change behavior by doing partial
+// specialization based on whether or not a parameter is a wrapper type.
+//
+// ConstRef() is similar to tr1::cref.  Unretained() is specific to Chromium.
+//
+//
+// WHY NOT TR1 FUNCTION/BIND?
+//
+// Direct use of tr1::function and tr1::bind was considered, but ultimately
+// rejected because of the number of copy constructors invocations involved
+// in the binding of arguments during construction, and the forwarding of
+// arguments during invocation.  These copies will no longer be an issue in
+// C++0x because C++0x will support rvalue reference allowing for the compiler
+// to avoid these copies.  However, waiting for C++0x is not an option.
+//
+// Measured with valgrind on gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5), the
+// tr1::bind call itself will invoke a non-trivial copy constructor three times
+// for each bound parameter.  Also, each when passing a tr1::function, each
+// bound argument will be copied again.
+//
+// In addition to the copies taken at binding and invocation, copying a
+// tr1::function causes a copy to be made of all the bound parameters and
+// state.
+//
+// Furthermore, in Chromium, it is desirable for the Callback to take a
+// reference on a target object when representing a class method call.  This
+// is not supported by tr1.
+//
+// Lastly, tr1::function and tr1::bind has a more general and flexible API.
+// This includes things like argument reordering by use of
+// tr1::bind::placeholder, support for non-const reference parameters, and some
+// limited amount of subtyping of the tr1::function object (e.g.,
+// tr1::function<int(int)> is convertible to tr1::function<void(int)>).
+//
+// These are not features that are required in Chromium. Some of them, such as
+// allowing for reference parameters, and subtyping of functions, may actually
+// become a source of errors. Removing support for these features actually
+// allows for a simpler implementation, and a terser Currying API.
+//
+//
+// WHY NOT GOOGLE CALLBACKS?
+//
+// The Google callback system also does not support refcounting.  Furthermore,
+// its implementation has a number of strange edge cases with respect to type
+// conversion of its arguments.  In particular, the argument's constness must
+// at times match exactly the function signature, or the type-inference might
+// break.  Given the above, writing a custom solution was easier.
+//
+//
+// MISSING FUNCTIONALITY
+//  - Invoking the return of Bind.  Bind(&foo).Run() does not work;
+//  - Binding arrays to functions that take a non-const pointer.
+//    Example:
+//      void Foo(const char* ptr);
+//      void Bar(char* ptr);
+//      Bind(&Foo, "test");
+//      Bind(&Bar, "test");  // This fails because ptr is not const.
+
+namespace base {
+
+// First, we forward declare the Callback class template. This informs the
+// compiler that the template only has 1 type parameter which is the function
+// signature that the Callback is representing.
+//
+// After this, create template specializations for 0-7 parameters. Note that
+// even though the template typelist grows, the specialization still
+// only has one type: the function signature.
+//
+// If you are thinking of forward declaring Callback in your own header file,
+// please include "base/callback_forward.h" instead.
+
+namespace internal {
+template <typename Runnable, typename RunType, typename... BoundArgsType>
+struct BindState;
+}  // namespace internal
+
+template <typename R, typename... Args>
+class Callback<R(Args...)> : public internal::CallbackBase {
+ public:
+  // MSVC 2013 doesn't support Type Alias of function types.
+  // Revisit this after we update it to newer version.
+  typedef R RunType(Args...);
+
+  Callback() : CallbackBase(nullptr) { }
+
+  template <typename Runnable, typename BindRunType, typename... BoundArgsType>
+  explicit Callback(
+      internal::BindState<Runnable, BindRunType, BoundArgsType...>* bind_state)
+      : CallbackBase(bind_state) {
+    // Force the assignment to a local variable of PolymorphicInvoke
+    // so the compiler will typecheck that the passed in Run() method has
+    // the correct type.
+    PolymorphicInvoke invoke_func =
+        &internal::BindState<Runnable, BindRunType, BoundArgsType...>
+            ::InvokerType::Run;
+    polymorphic_invoke_ = reinterpret_cast<InvokeFuncStorage>(invoke_func);
+  }
+
+  bool Equals(const Callback& other) const {
+    return CallbackBase::Equals(other);
+  }
+
+  R Run(typename internal::CallbackParamTraits<Args>::ForwardType... args)
+      const {
+    PolymorphicInvoke f =
+        reinterpret_cast<PolymorphicInvoke>(polymorphic_invoke_);
+
+    return f(bind_state_.get(), internal::CallbackForward(args)...);
+  }
+
+ private:
+  using PolymorphicInvoke =
+      R(*)(internal::BindStateBase*,
+           typename internal::CallbackParamTraits<Args>::ForwardType...);
+};
+
+}  // namespace base
+
+#endif  // BASE_CALLBACK_H_