Allow resizing pip window

src/FlightDisplay/FlightDisplayView.qml

@@ -311,6 +311,24 @@ QGCView {
             onHideIt: {
                 setPipVisibility(!state)
             }
+            onBigger: {
+                if (_pipSize >= 825) {
+                    return
+                }
+
+                _pipSize += 50
+                _flightVideoPipControl.width = _pipSize
+                _flightVideoPipControl.height= _pipSize * (9/16)
+            }
+            onSmaller: {
+                if (_pipSize <= 225) {
+                    return
+                }
+
+                _pipSize -= 50
+                _flightVideoPipControl.width = _pipSize
+                _flightVideoPipControl.height= _pipSize * (9/16)
+            }
         }
 
         Row {

src/QmlControls/QGCPipable.qml

@@ -24,6 +24,8 @@ Item {
 
     signal  activated()
     signal  hideIt(bool state)
+    signal  bigger()
+    signal  smaller()
 
     MouseArea {
         anchors.fill: parent
@@ -33,6 +35,32 @@ Item {
         }
     }
 
+    QGCButton {
+        id: largerButton
+        visible: !isHidden
+        anchors.left: parent.left
+        anchors.bottom: smallerButton.top
+        height: 20
+        width: height
+        anchors.margins: 5
+        text: "+"
+        opacity: 0.5
+        onClicked: pip.bigger()
+    }
+
+    QGCButton {
+        id: smallerButton
+        visible: !isHidden
+        anchors.left: parent.left
+        anchors.bottom: closePIP.top
+        height: 20
+        width: height
+        anchors.margins: 5
+        text: "-"
+        opacity: 0.5
+        onClicked: pip.smaller()
+    }
+
     //-- PIP Corner Indicator
     Image {
         id:             closePIP