Doc: Fix QtWebEngine version number

The latest version for Qt Webengine in 5.9 will be 1.5, not 1.6.

Change-Id: Ibae42f24f4b7477901923ff0ef5436642599f365
Reviewed-by: Viktor Engelmann <viktor.engelmann@qt.io>
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

src/webengine/api/qquickwebenginedownloaditem.cpp

@@ -368,7 +368,7 @@ QQuickWebEngineDownloadItem::DownloadType QQuickWebEngineDownloadItem::type() co
 /*!
     \qmlproperty enumeration WebEngineDownloadItem::interruptReason
     \readonly
-    \since QtWebEngine 1.6
+    \since QtWebEngine 1.5
 
     Returns the reason why the download was interrupted:
 
@@ -416,7 +416,7 @@ QQuickWebEngineDownloadItem::DownloadInterruptReason QQuickWebEngineDownloadItem
 /*!
     \qmlproperty string WebEngineDownloadItem::interruptReasonString
     Returns a human-readable description of the reason for interrupting the download.
-    \since QtWebEngine 1.6
+    \since QtWebEngine 1.5
 
     \sa interruptReason
 */

src/webengine/api/qquickwebenginenewviewrequest.cpp

@@ -74,7 +74,7 @@ QQuickWebEngineView::NewViewDestination QQuickWebEngineNewViewRequest::destinati
 /*!
     \qmlproperty QUrl WebEngineNewViewRequest::requestedUrl
     The URL that is requested by the page.
-    \since QtWebEngine 1.6
+    \since QtWebEngine 1.5
  */
 QUrl QQuickWebEngineNewViewRequest::requestedUrl() const
 {