QmlDesigner: Add a default validator to ItemFilterComboBox

Change-Id: Iba8f3f42d7028bc5da5b5abd6d3581f67184376b
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>
Reviewed-by: Henning Gründl <henning.gruendl@qt.io>

share/qtcreator/qmldesigner/propertyEditorQmlSources/QtMultimedia/MediaPlayerSection.qml

@@ -49,7 +49,6 @@ Section {
                                + StudioTheme.Values.actionIndicatorWidth
                 width: implicitWidth
                 typeFilter: "QtQuick.AudioOutput"
-                validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                 backendValue: backendValues.audioOutput
             }
 
@@ -70,7 +69,6 @@ Section {
                                + StudioTheme.Values.actionIndicatorWidth
                 width: implicitWidth
                 typeFilter: "QtQuick.VideoOutput"
-                validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                 backendValue: backendValues.videoOutput
             }
 

share/qtcreator/qmldesigner/propertyEditorQmlSources/QtQuick/AnimationTargetSection.qml

@@ -23,7 +23,6 @@ Section {
         SecondColumnLayout {
             ItemFilterComboBox {
                 typeFilter: "QtQuick.QtObject"
-                validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                 backendValue: backendValues.target
                 implicitWidth: StudioTheme.Values.singleControlColumnWidth
                                + StudioTheme.Values.actionIndicatorWidth

share/qtcreator/qmldesigner/propertyEditorQmlSources/QtQuick/ConnectionsSpecifics.qml

@@ -52,7 +52,6 @@ Section {
         SecondColumnLayout {
             ItemFilterComboBox {
                 typeFilter: "QtQuick.Item"
-                validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                 backendValue: backendValues.target
                 implicitWidth: StudioTheme.Values.singleControlColumnWidth
                                + StudioTheme.Values.actionIndicatorWidth

share/qtcreator/qmldesigner/propertyEditorQmlSources/QtQuick/LayerSection.qml

@@ -100,7 +100,6 @@ Section {
                                + StudioTheme.Values.actionIndicatorWidth
                 width: implicitWidth
                 typeFilter: "QtQuick.Item"
-                validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                 backendValue: backendValues.layer_effect
             }
 

share/qtcreator/qmldesigner/propertyEditorQmlSources/QtQuick/LoaderSpecifics.qml

@@ -55,7 +55,6 @@ Column {
             SecondColumnLayout {
                 ItemFilterComboBox {
                     typeFilter: "Component"
-                    validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                     backendValue: backendValues.sourceComponent
                     implicitWidth: StudioTheme.Values.singleControlColumnWidth
                                    + StudioTheme.Values.actionIndicatorWidth

share/qtcreator/qmldesigner/propertyEditorQmlSources/QtQuick/MouseAreaSpecifics.qml

@@ -181,7 +181,6 @@ Column {
             SecondColumnLayout {
                 ItemFilterComboBox {
                     typeFilter: "QtQuick.QtObject"
-                    validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                     backendValue: backendValues.drag_target
                     implicitWidth: StudioTheme.Values.singleControlColumnWidth
                                    + StudioTheme.Values.actionIndicatorWidth

share/qtcreator/qmldesigner/propertyEditorQmlSources/QtQuick/RepeaterSpecifics.qml

@@ -42,7 +42,6 @@ Column {
             SecondColumnLayout {
                 ItemFilterComboBox {
                     typeFilter: "Component"
-                    validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                     backendValue: backendValues.delegate
                     implicitWidth: StudioTheme.Values.singleControlColumnWidth
                                    + StudioTheme.Values.actionIndicatorWidth

share/qtcreator/qmldesigner/propertyEditorQmlSources/QtQuick3D/SpatialAudio/AudioEngineSection.qml

@@ -55,7 +55,6 @@ Section {
         SecondColumnLayout {
             ItemFilterComboBox {
                 typeFilter: "QtMultimedia.AudioDevice"
-                validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                 backendValue: backendValues.outputDevice
                 implicitWidth: StudioTheme.Values.singleControlColumnWidth
                                + StudioTheme.Values.actionIndicatorWidth

share/qtcreator/qmldesigner/propertyEditorQmlSources/imports/HelperWidgets/DynamicPropertiesSection.qml

@@ -266,7 +266,6 @@ Section {
 
             ItemFilterComboBox {
                 typeFilter: "QtQuick3D.TextureInput"
-                validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
                 backendValue: layoutTextureInput.backendValue
                 implicitWidth: StudioTheme.Values.singleControlColumnWidth
                                + StudioTheme.Values.actionIndicatorWidth

share/qtcreator/qmldesigner/propertyEditorQmlSources/imports/HelperWidgets/ItemFilterComboBox.qml

@@ -13,6 +13,8 @@ HelperWidgets.ComboBox {
     editable: true
     model: comboBox.addDefaultItem(itemFilterModel.itemModel)
 
+    validator: RegExpValidator { regExp: /(^$|^[a-z_]\w*)/ }
+
     HelperWidgets.ItemFilterModel {
         id: itemFilterModel
         modelNodeBackendProperty: modelNodeBackend