This commit fixes a situation reported by a user where two indexes
contained information about the same pack without overlap, e.g.:
Index 3e6a32 contained:
{
"id": "c02e3b",
"blobs": [
{
"id": "8114b1",
"type": "data",
"offset": 0,
"length": 530107
}
]
}
And index 62da5f contained:
{
"id": "c02e3b",
"blobs": [
{
"id": "e344f8",
"type": "data",
"offset": 1975848,
"length": 3426468
},
{
"id": "939ed9",
"type": "data",
"offset": 530107,
"length": 1445741
}
]
}
This commit adds all blobs in a pack in one atomic operation so that
intermediate such as these do not happen.
567de35df4