Q{File,Font,Color,Message}DialogOptions are no value classes

These classes are only held in QSharedPointer, so optimize for that:

1. Disable default ctor, copy ctor and assignment operator,
   destructor and swap for public users.
2. Add create() to return an instance in a shared pointer.
3. Allocate public and private classes in one memory block,
   use QSharedPointer::create() to also add the QSharedPointer
   control block to the same memory allocation.

As a consequence, this reduces the creation of a Q*DialogOptions
into a shared pointer by two memory allocations.

Add a macro to enable atomic updates to QtQuick and other users
outside QtBase.

[ChangeLog][QtGui]
[QFileDialogOptions/QFontDialogOptions/QMessageDialogOptions/QColorDialogOptions]
This class no longer has value semantics, but needs to be held
in QSharedPointer (as it always was). To copy an instance, use
the clone() method.

Change-Id: I4c81220e0a8286a310df1c224a30eca34824c4e6
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@theqtcompany.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/widgets/dialogs/qfiledialog.cpp b/src/widgets/dialogs/qfiledialog.cpp
index 50667e2a91..3bcd6f7c4b 100644
--- a/src/widgets/dialogs/qfiledialog.cpp
+++ b/src/widgets/dialogs/qfiledialog.cpp
@@ -533,7 +533,7 @@ QFileDialogPrivate::QFileDialogPrivate()
         showHiddenAction(0),
         useDefaultCaption(true),
         qFileDialogUi(0),
-        options(new QFileDialogOptions)
+        options(QFileDialogOptions::create())
 {
 }