Currently, when the coordIndex attribute of an IndexedLineSet contains a
polyline with > 2 indices, X3DGeoHelper::coordIdx_str2faces_arr() will
incorrectly determine the primitive type to be aiPrimitiveType_TRIANGLE or
aiPrimitiveType_POLYGON instead of aiPrimitiveType_LINE.
To fix this, this commit adds functions to explicitly handle an IndexedLineSet.
Fixes#3101
==23896==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x12f9daec1827 at pc 0x7ffcad83699c bp 0x00c61574c910 sp 0x00c61574c910
READ of size 1 at 0x12f9daec1827 thread T0
==23896==WARNING: Failed to use and restart external symbolizer!
#0 0x7ffcad83699b in Assimp::IOStreamBuffer<char>::getNextLine C:\Users\aavenel\Dev\assimp\include\assimp\IOStreamBuffer.h:299
#1 0x7ffcad83ce69 in Assimp::PLY::DOM::ParseHeader C:\Users\aavenel\Dev\assimp\code\AssetLib\Ply\PlyParser.cpp:428
#2 0x7ffcad83d58e in Assimp::PLY::DOM::ParseInstanceBinary C:\Users\aavenel\Dev\assimp\code\AssetLib\Ply\PlyParser.cpp:498
#3 0x7ffcad83302a in Assimp::PLYImporter::InternReadFile C:\Users\aavenel\Dev\assimp\code\AssetLib\Ply\PlyLoader.cpp:189
#4 0x7ffcad4f2f48 in Assimp::BaseImporter::ReadFile C:\Users\aavenel\Dev\assimp\code\Common\BaseImporter.cpp:135
#5 0x7ffcad51ee46 in Assimp::Importer::ReadFile C:\Users\aavenel\Dev\assimp\code\Common\Importer.cpp:709
#6 0x7ff7dd8f9f1a in ImportModel C:\Users\aavenel\Dev\assimp\tools\assimp_cmd\Main.cpp:307
#7 0x7ff7dd8fdf9e in Assimp_Info C:\Users\aavenel\Dev\assimp\tools\assimp_cmd\Info.cpp:344
#8 0x7ff7dd8fc04f in main C:\Users\aavenel\Dev\assimp\tools\assimp_cmd\Main.cpp:222
#9 0x7ff7dd9030eb in __scrt_common_main_seh D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288
#10 0x7ffd39e57343 in BaseThreadInitThunk+0x13 (C:\WINDOWS\System32\KERNEL32.DLL+0x180017343)
#11 0x7ffd3a2626b0 in RtlUserThreadStart+0x20 (C:\WINDOWS\SYSTEM32\ntdll.dll+0x1800526b0)
The regression was introduced in 904f17f.
Since all the cases are now fully handled at the child level,
visiting the whole subtree is changed into iteration over the children.