Async: Replace make_future/make_shared_future by make_ready_future

[viboes]

template <typename T>
future<typename decay<T>::type> make_ready_future(T&& value);  
future<void> make_ready_future();
template <typename T>
future<T> make_ready_future(exception_ptr ex);
template <typename T, typename E>
future<T> make_ready_future(E ex);

Effects:

• value prototype: The value that is passed into the function is moved to the shared state of the returned function if it is an rvalue. Otherwise the value is copied to the shared state of the returned function.

• exception: The exception that is passed into the function is copied to the shared state of the returned function.

Returns:

• a ready future with the value set with value

• a ready future with the exception set with ex

• a ready future<void> with the value set (void).

Postcondition:

• Returned future, valid() == true

• Returned future, is_ready() = true

• Returned future, has_value() = true or has_exception() depending on the prototype.

[viboes]

Committed revision [84493].

[viboes]

Changeset [85200]