Add changes file for Qt 5.12.3

+ 16836da1ae Page: fix binding loop
+ feed3b7b80 Drawer: fix infinite positioning loop
+ fa641ab123 Add dialogs manual test
+ 951bfc041f Doc: restructure and fill in Imagine customization section
+ d45d163240 Doc: state that negative scales for Popup are not supported
+ 637630cc7e Remove the internal_module config to enable generation of cmake files
+ 05eb812759 QQuickMenu: allow enter/return to be used to activate items
+ 694438066e qtlite: Fix build the source code with -no-feature-shortcut
+ 9fdbdea176 Fix tst_cursor::controls(containers) test failing after change in the Windows QPA
+ ff30fc5f5f QQuickScrollView: respect the content size set on/by the flickable
+ 73914e00db Add *.pro.user.* to .gitignore
+ 1ef176b5da Fix attached ToolTips using the timeout of the last shown tool tip
+ 8b78d9cea3 Fix DialogButtonBox content size calculation
+ 0ee25027ed Handle recursion depth errors in tst_sanity.cpp
+ 27e030f24b Bump version
+ 5a07a970fa QQuickComboBox: ensure we don't close popup on iOS
+ 5135bec507 DialogButtonBox: don't sort buttons based on their memory addresses
+ 11995169ee Mark BaseValidator::throwRecursionDepthError() as final
+ 10023b188b Default: fix highlighted ItemDelegate colors
+ d0f6b28618 Fix typo in ScrollBar's documentation
+ 7c31b884b9 Attempt to stabilize Tumbler::test_itemsCorrectlyPositioned
+ ef9ab1a4bd tst_dialogbuttonbox.qml: use tryVerify() consistently to avoid flakiness
+ 1bb25edd6c tst_dialogbuttonbox.qml: consolidate two similar tests

Change-Id: I32bc2dc040808d8b556e5231e1d2b77a50138b4e
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

dist/changes-5.12.3

@@ -0,0 +1,46 @@
+Qt 5.12.3 is a bug-fix release. It maintains both forward and backward
+compatibility (source and binary) with Qt 5.12.0 through 5.12.2.
+
+For more details, refer to the online documentation included in this
+distribution. The documentation is also available online:
+
+  https://doc.qt.io/qt-5/index.html
+
+The Qt version 5.12 series is binary compatible with the 5.11.x series.
+Applications compiled for 5.11 will continue to run with 5.12.
+
+Some of the changes listed in this file include issue tracking numbers
+corresponding to tasks in the Qt Bug Tracker:
+
+  https://bugreports.qt.io/
+
+Each of these identifiers can be entered in the bug tracker to obtain more
+information about a particular change.
+
+****************************************************************************
+*                          Controls                                        *
+****************************************************************************
+
+ - [QTBUG-70451] DialogButtonBox: fixed buttons with equal roles being
+   randomly sorted.
+ - [QTBUG-70161] ComboBox: fixed popup immediately closing on iOS
+ - [QTBUG-72886] DialogButtonBox: fixed content size calculation
+ - [QTBUG-74226] Fixed attached ToolTips using the timeout of the last shown
+   tool tip
+ - [QTBUG-72536] ScrollView now respects the content size set on/by
+   the flickable
+ - [QTBUG-73354] Menu: enter/return can now be used to activate items,
+   rather than just space.
+ - [QTBUG-71290] Drawer: fixed infinite positioning loop
+ - [QTBUG-66494] Page: fixed binding loop
+
+****************************************************************************
+*                          Styles                                          *
+****************************************************************************
+
+Default
+--------
+ - [QTBUG-72786] Made ItemDelegate respect highlightedText and improved
+   highlightedText color so that text shows up against a highlighted background.
+   This also allows easily switching ComboBox to a dark style via palette
+   customization.