Fix typos in the documentation

Returnes -> returns

Change-Id: I52372488a16d7c13e85fca0e11eaab738db9355d
Reviewed-by: Jesus Fernandez <Jesus.Fernandez@qt.io>

src/gui/kernel/qplatformscreen.cpp

@@ -72,7 +72,7 @@ QPlatformScreen::~QPlatformScreen()
 
     This function is called when Qt needs to be able to grab the content of a window.
 
-    Returnes the content of the window specified with the WId handle within the boundaries of
+    Returns the content of the window specified with the WId handle within the boundaries of
     QRect(x,y,width,height).
 */
 QPixmap QPlatformScreen::grabWindow(WId window, int x, int y, int width, int height) const

src/gui/kernel/qplatformwindow.cpp

@@ -140,7 +140,7 @@ void QPlatformWindow::setGeometry(const QRect &rect)
 }
 
 /*!
-    Returnes the current geometry of a window
+    Returns the current geometry of a window
 */
 QRect QPlatformWindow::geometry() const
 {

src/network/access/qnetworkaccessmanager.cpp

@@ -930,7 +930,7 @@ QNetworkReply *QNetworkAccessManager::put(const QNetworkRequest &request, QHttpM
 
 /*!
     Uploads the contents of \a data to the destination \a request and
-    returnes a new QNetworkReply object that will be open for reply.
+    returns a new QNetworkReply object that will be open for reply.
 
     \a data must be opened for reading when this function is called
     and must remain valid until the finished() signal is emitted for

src/platformheaders/cocoafunctions/qcocoawindowfunctions.qdoc

@@ -46,7 +46,7 @@
 /*!
     \fn QByteArray QCocoaWindowFunctions::bottomLeftClippedByNSWindowOffsetIdentifier()
 
-    This function returnes the bytearray that can be used to query
+    This function returns the bytearray that can be used to query
     QGuiApplication::platformFunction to retrieve the BottomLeftClippedByNSWindowOffset function.
 */