Merge pull request #8811 from patrickelectric/qt_5_15

src/Camera/QGCCameraControl.cc

src/FactSystem/FactMetaData.cc

src/FactSystem/FactMetaData.h

src/FirmwarePlugin/APM/APMFirmwarePlugin.cc

src/JsonHelper.cc

src/LogCompressor.cc

src/MissionManager/ComplexMissionItem.cc

src/MissionManager/MissionCommandUIInfo.cc

src/MissionManager/QGCMapPolygon.cc

src/MissionManager/QGCMapPolyline.cc

src/MissionManager/SurveyComplexItem.cc

src/QGCComboBox.cc

src/QGCFileDownload.cc

src/QGCTemporaryFile.cc

src/QmlControls/ParameterEditorController.cc

src/QmlControls/QGroundControlQmlGlobal.cc

src/QtLocationPlugin/GoogleMapProvider.cpp

src/QtLocationPlugin/QGCMapTileSet.cpp

src/Settings/AppSettings.cc

src/Terrain/TerrainQuery.cc