QML UI: scroll to top of dive list when tapping title bar

This helps you get to the latest dive when you are stuck at the bottom
of a dive list.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-mobile/qml/DiveList.qml

@@ -14,6 +14,11 @@ MobileComponents.Page {
 	property int credentialStatus: manager.credentialStatus
 	property int numDives: diveListView.count
 	property color textColor: subsurfaceTheme.diveListTextColor
+
+	function scrollToTop() {
+		diveListView.positionViewAtBeginning()
+	}
+
 	Component {
 		id: diveDelegate
 		MobileComponents.ListItem {

qt-mobile/qml/TopBar.qml

@@ -48,4 +48,12 @@ Rectangle {
 			Layout.fillWidth: true
 		}
 	}
+	MouseArea {
+		anchors.fill: topPart
+		onClicked: {
+			if (stackView.depth == 1 && showingDiveList) {
+				scrollToTop()
+			}
+		}
+	}
 }

qt-mobile/qml/main.qml

@@ -38,6 +38,10 @@ MobileComponents.ApplicationWindow {
 		detailsWindow.endEditMode()
 	}
 
+	function scrollToTop() {
+		diveList.scrollToTop()
+	}
+
 	globalDrawer: MobileComponents.GlobalDrawer {
 		title: "Subsurface"
 		titleIcon: "qrc:/qml/subsurface-mobile-icon.png"