This test runs the WebGL Test listed below in an iframe and reports PASS or FAIL.

Test: ../../../resources/webgl_test_files/deqp/functional/gles3/fbostencilbuffer.html
[ 1: FAIL ] stencil.basic.depth32f_stencil8: glError: INVALID_ENUM
[ 2: FAIL ] stencil.basic.depth32f_stencil8_depth: glError: INVALID_ENUM
[ 3: FAIL ] stencil.basic.depth24_stencil8: glError: INVALID_ENUM
[ 4: FAIL ] stencil.basic.depth24_stencil8_depth: glError: INVALID_ENUM
[ 5: FAIL ] stencil.basic.stencil_index8:
[ 6: FAIL ] stencil.attach.depth_only: glError: INVALID_ENUM
[ 7: FAIL ] stencil.attach.stencil_only: glError: INVALID_ENUM
[ 8: FAIL ] stencil.attach.depth_stencil_separate: glError: INVALID_ENUM
[ 9: FAIL ] stencil.attach.depth_stencil_attachment: glError: INVALID_ENUM
[ 10: PASS ] stencil.attach.depth_stencil_attachment: successfullyParsed is true
[ FAIL ] 9 failures reported