Fix regression in QWaylandGlContext::makeCurrent for offscreen surfaces

[ChangeLog][QPA plugin] Fixed a bug where offscreen surfaces would get
surfaceless EGL contexts.

Fixes a regression in in bf09c7a1.

The call, window->updateSurface(window->isExposed()), is problematic because
offscreen textures are never exposed, and consequently, eglSurface will be
EGL_NO_SURFACE, which will then create a surfaceless context in the call:

    eglMakeCurrent(m_eglDisplay, eglSurface, eglSurface, m_context)

This reverts to the old behavior of always trying to create an EGL surface,
unless the window doesn't have a valid wl_surface, in which case it doesn't
make sense (which is what bf09c7a1 fixed, QTBUG-65553).

Task-number: QTBUG-70242
Task-number: QTBUG-68605
Task-number: QTBUG-67601
Change-Id: I44b07bb8bf4b33c73c6379a1de8e9e5cfd220b51
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>
(cherry picked from commit 192b2e8f59e7f0cb3c2d482524bf171a81a213c5)

2 files changed, 7 insertions, 4 deletions

diff --git a/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow.cpp b/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow.cpp
index 20cc8bd9f..e4da26133 100644
--- a/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow.cpp
+++ b/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow.cpp
@@ -132,13 +132,16 @@ void QWaylandEglWindow::updateSurface(bool create)
 
                 m_resize = true;
             }
-        } else if (create) {
-            m_waylandEglWindow = wl_egl_window_create(object(), sizeWithMargins.width(), sizeWithMargins.height());
+        } else if (create && wl_surface::isInitialized()) {
+            ::wl_surface *wlSurface = wl_surface::object();
+            m_waylandEglWindow = wl_egl_window_create(wlSurface, sizeWithMargins.width(), sizeWithMargins.height());
         }
 
-        if (!m_eglSurface && create) {
+        if (!m_eglSurface && m_waylandEglWindow && create) {
             EGLNativeWindowType eglw = (EGLNativeWindowType) m_waylandEglWindow;
             m_eglSurface = eglCreateWindowSurface(m_clientBufferIntegration->eglDisplay(), m_eglConfig, eglw, 0);
+            if (Q_UNLIKELY(m_eglSurface == EGL_NO_SURFACE))
+                qWarning("QtWayland: Could not create EGL surface (EGL error 0x%x)\n", eglGetError());
         }
     }
 }
diff --git a/src/hardwareintegration/client/wayland-egl/qwaylandglcontext.cpp b/src/hardwareintegration/client/wayland-egl/qwaylandglcontext.cpp
index f4dd6f492..2a9e39ed6 100644
--- a/src/hardwareintegration/client/wayland-egl/qwaylandglcontext.cpp
+++ b/src/hardwareintegration/client/wayland-egl/qwaylandglcontext.cpp
@@ -407,7 +407,7 @@ bool QWaylandGLContext::makeCurrent(QPlatformSurface *surface)
         window->createDecoration();
 
     if (eglSurface == EGL_NO_SURFACE) {
-        window->updateSurface(window->isExposed());
+        window->updateSurface(true);
         eglSurface = window->eglSurface();
     }