Patch to print EGL/GL errors around eglSwapBuffers calls in QtUbuntu

debug.patch

diff --git a/src/ubuntumirclient/qmirclientglcontext.cpp b/src/ubuntumirclient/qmirclientglcontext.cpp
index 3c67461..5f78e59 100644
--- a/src/ubuntumirclient/qmirclientglcontext.cpp
+++ b/src/ubuntumirclient/qmirclientglcontext.cpp
@@ -47,6 +47,8 @@
 #include <QtEglSupport/private/qeglpbuffer_p.h>
 #include <QtGui/private/qopenglcontext_p.h>
 
+#include <QElapsedTimer>
+
 Q_LOGGING_CATEGORY(mirclientGraphics, "qt.qpa.mirclient.graphics", QtWarningMsg)
 
 namespace {
@@ -122,11 +124,41 @@ EGLSurface QMirClientOpenGLContext::eglSurfaceForPlatformSurface(QPlatformSurfac
 
 void QMirClientOpenGLContext::swapBuffers(QPlatformSurface *surface)
 {
+    QElapsedTimer timer;
+    EGLint error = EGL_SUCCESS;
+    do {
+        error = eglGetError();
+        qDebug() << "BEFORE!";
+        if (error != EGL_SUCCESS) {
+            qDebug() << "EGL ERROR BEFORE!" << error;
+        }
+    } while (error != EGL_SUCCESS);
+    GLenum glerror = GL_NO_ERROR;
+    do {
+        glerror = glGetError();
+        if (glerror != GL_NO_ERROR)
+            qDebug() << "GL ERROR BEFORE!" << glerror;
+    } while (glerror != GL_NO_ERROR);
+
+    timer.start();
     QEGLPlatformContext::swapBuffers(surface);
+    qDebug() << "AFTER!" << timer.elapsed();
 
     if (surface->surface()->surfaceClass() == QSurface::Window) {
         // notify window on swap completion
         auto platformWindow = static_cast<QMirClientWindow *>(surface);
         platformWindow->onSwapBuffersDone();
     }
+
+    do {
+        glerror = glGetError();
+        if (glerror != GL_NO_ERROR)
+            qDebug() << "GL ERROR BEFORE!" << glerror;
+    } while (glerror != GL_NO_ERROR);
+    do {
+        error = eglGetError();
+        if (error != EGL_SUCCESS) {
+            qDebug() << "EGL ERROR AFTER!" << error;
+        }
+    } while (error != EGL_SUCCESS);
 }