Entities don't catch on fire when inside lava fluid states

This is caused by checking if the block is lava, rather than if the fluid state is lava in World.isFlamableWithin(AxisAlignedBB) (MCP), World.doesAreaContainFireSource(BoundingBox) (Yarn), axy.b(Lcea;)Z (obf). The following code that does this check

IBlockState state = this.getBlockState(blockpos$pooledmutableblockpos.setPos(k1, l1, i2));
Block block = state.getBlock();
if (block == Blocks.FIRE || block == Blocks.LAVA) { // <--- This checks if the block is lava. Due to the addition of fluid states, there can be a lava fluid at the pos, but the block may not be lava.
 return true;
}

could be changed to check the fluid state instead.