Assert on brit_hero_caratacos.png

[nwtour]

If start game compiled config=debug and select "Brits" in the Structures overview get assert:

Function call failed: return value was -100113 (Case 13)
Location: ogl_tex.cpp:505 (OglTex_validate)

GDB backtrace:

#0  raise (sig=<optimized out>) at ../sysdeps/unix/sysv/linux/raise.c:50
#1  0x08a6861f in debug_break () at ../../../source/lib/sysdep/os/unix/udbg.cpp:51
#2  0x08a54e78 in OglTex_validate (ot=0xb1c87158) at ../../../source/lib/res/graphics/ogl_tex.cpp:505
#3  0x08a57b9a in warn_if_invalid (hd=0xb1c87120) at ../../../source/lib/res/h_mgr.cpp:353
#4  0x08a58008 in call_init_and_reload (h=26935478, type=0x9130dc8 <V_OglTex>, hd=0xb1c87120, vfs=std::shared_ptr<struct IVFS> (use count 4, weak count 0) = {...}, pathname=...,
    init_args=0xbfffece8) at ../../../source/lib/res/h_mgr.cpp:440
#5  0x08a58261 in alloc_new_handle (type=0x9130dc8 <V_OglTex>, vfs=std::shared_ptr<struct IVFS> (use count 4, weak count 0) = {...}, pathname=..., key=1392861520, flags=17,
    init_args=0xbfffece8) at ../../../source/lib/res/h_mgr.cpp:481
#6  0x08a58419 in h_alloc (type=0x9130dc8 <V_OglTex>, vfs=std::shared_ptr<struct IVFS> (use count 4, weak count 0) = {...}, pathname=..., flags=17) at ../../../source/lib/res/h_mgr.cpp:518
#7  0x08a5519e in ogl_tex_load (vfs=std::shared_ptr<struct IVFS> (use count 4, weak count 0) = {...}, pathname=..., flags=17) at ../../../source/lib/res/graphics/ogl_tex.cpp:544
#8  0x08787e06 in CTextureManagerImpl::LoadTexture (this=0x95dcd90, texture=std::shared_ptr<class CTexture> (use count 4, weak count 9) = {...}, path=...)
    at ../../../source/graphics/TextureManager.cpp:179

The problem with the brit_hero_caratacos.png file. It has a non-standard geometry.

$ file binaries/data/mods/public/art/textures/ui/session/portraits/units/* | grep -v 256 | grep -v 128
binaries/data/mods/public/art/textures/ui/session/portraits/units/brit_hero_caratacos.png:                    PNG image, 220 x 220, 8-bit/color RGBA, non-interlaced

Converting it to 128x128 resolution solves the problem (convert -resize 128x128)

[Stan]

In 25437:

Fix broken non pot texture by @m7600

Reported by: @nwtour

Fixes: #6177 and ​Phab:rP25237