QmlDesigner.propertyEditor: fix glitch on Mac

share/qtcreator/qmldesigner/propertyeditor/Qt/AlignmentHorizontalButtons.qml

@@ -13,7 +13,9 @@ QGroupBox {
                 id: leftButton
                 checkable: true
                 fixedWidth: 32
+				width: fixedWidth
                 fixedHeight: 32
+				height: fixedHeight
                 styleSheetFile: "alignmentleftbutton.css";
                 checked: backendValues.horizontalAlignment.value == "AlignLeft"
 
@@ -30,7 +32,9 @@ QGroupBox {
                 x: 32
                 checkable: true
                 fixedWidth: 32
+				width: fixedWidth
                 fixedHeight: 32
+				height: fixedHeight
 
                 styleSheetFile: "alignmentcenterhbutton.css";
                 checked: backendValues.horizontalAlignment.value == "AlignHCenter"
@@ -48,7 +52,9 @@ QGroupBox {
                 x: 64
                 checkable: true
                 fixedWidth: 32
+				width: fixedWidth
                 fixedHeight: 32
+				height: fixedHeight
 
                 styleSheetFile: "alignmentrightbutton.css";
                 checked: backendValues.horizontalAlignment.value == "AlignRight"

share/qtcreator/qmldesigner/propertyeditor/Qt/AlignmentVerticalButtons.qml

@@ -14,6 +14,8 @@ QGroupBox {
                 checkable: true
                 fixedWidth: 32
                 fixedHeight: 32
+				width: fixedWidth
+				height: fixedHeight
                 styleSheetFile: "alignmenttopbutton.css";
                 checked: backendValues.verticalAlignment.value == "AlignTop"
 
@@ -31,6 +33,8 @@ QGroupBox {
                 checkable: true
                 fixedWidth: 32
                 fixedHeight: 32
+				width: fixedWidth
+				height: fixedHeight
 
                 styleSheetFile: "alignmentcentervbutton.css";
                 checked: backendValues.verticalAlignment.value == "AlignVCenter"
@@ -49,6 +53,8 @@ QGroupBox {
                 checkable: true
                 fixedWidth: 32
                 fixedHeight: 32
+				width: fixedWidth
+				height: fixedHeight
 
                 styleSheetFile: "alignmentbottombutton.css";
                 checked: backendValues.verticalAlignment.value == "AlignBottom"