Remove GLVertextBuffer::setVirtualScreenSize

Marked for removal with next ABI break. Which happened with
ea52ef9e57

libkwineffects/kwinglutils.cpp

@@ -2024,7 +2024,6 @@ GLvoid *GLVertexBufferPrivate::mapNextFreeRange(size_t size)
 //*********************************
 // GLVertexBuffer
 //*********************************
-QSize GLVertexBuffer::s_virtualScreenSize;
 QRect GLVertexBuffer::s_virtualScreenGeometry;
 
 GLVertexBuffer::GLVertexBuffer(UsageHint hint)

libkwineffects/kwinglutils.h

@@ -775,15 +775,6 @@ public:
      **/
     static GLVertexBuffer *streamingBuffer();
 
-    /**
-     * Sets the virtual screen size to @p s.
-     * @since 5.2
-     * @deprecated since 5.9 use setVirtualScreenGeometry
-     **/
-    static void KWINGLUTILS_DEPRECATED setVirtualScreenSize(const QSize &s) {
-        s_virtualScreenSize = s;
-    }
-
     /**
      * Sets the virtual screen geometry to @p g.
      * This is the geometry of the OpenGL window currently being rendered to
@@ -796,8 +787,6 @@ public:
 
 private:
     GLVertexBufferPrivate* const d;
-    // TODO: remove with next ABI break
-    static QSize s_virtualScreenSize;
     static QRect s_virtualScreenGeometry;
 };