/usr/include/x86_64-linux-gnu/ is in libqt5opengl5-gles-dev 5.5.1+dfsg-16ubuntu6.
This file is owned by root:root, with mode 0o755.
..
/usr/include/x86_64-linux-gnu/qt5/
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGL
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLBuffer
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLColormap
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLContext
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLFormat
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLFramebufferObject
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLFramebufferObjectFormat
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLFunctions
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLFunctionsPrivate
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLPixelBuffer
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLShader
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLShaderProgram
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QGLWidget
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QtOpenGL
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QtOpenGLDepends
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/QtOpenGLVersion
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/qgl.h
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/qglbuffer.h
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/qglcolormap.h
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/qglframebufferobject.h
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/qglfunctions.h
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/qglpixelbuffer.h
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/qglshaderprogram.h
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/qtopenglglobal.h
/usr/include/x86_64-linux-gnu/qt5/QtOpenGL/qtopenglversion.h