I'm not sure whether this is intentional, but it appears CP never deletes minidumps:

C:\src\syzygy\src\syzygy>dir "c:\users\siggi\AppData\Local\Google\Chrome SxS\User Data\Crashpad\reports"\*
 Volume in drive C has no label.
 Volume Serial Number is 824F-EA5A

 Directory of c:\users\siggi\AppData\Local\Google\Chrome SxS\User Data\Crashpad\reports

03/21/2016  09:38 AM    <DIR>          .
03/21/2016  09:38 AM    <DIR>          ..
01/21/2016  10:47 AM           932,432 0270d88a-7728-4562-b0d3-b4f73c380cf7.dmp
01/06/2016  04:38 PM           763,792 05e56a37-3547-4b4d-9068-23c3fb3d896d.dmp
01/18/2016  09:35 AM           180,304 06e2fc18-624f-4921-9989-84895987f28a.dmp
01/13/2016  10:22 AM            91,920 08362e43-d745-422a-9db3-509d8de72f4c.dmp
01/07/2016  02:36 PM           178,352 083dcea8-057b-4904-b2d6-d793a3c38b65.dmp
01/11/2016  09:53 AM           110,528 0e003351-32c1-49bd-a4dc-ebc64aadef61.dmp
03/16/2016  10:41 AM           541,392 0f42a892-6942-4303-9998-b414232cae21.dmp
03/16/2016  10:41 AM        25,912,320 136a31c7-9fc2-43b5-aeaf-a2bfde7f8ea4.dmp
01/12/2016  03:40 PM           177,968 1789618d-10f4-4563-a03a-29ec75ee028f.dmp
03/21/2016  09:38 AM           588,544 1e61ccfb-982e-4976-8964-2a6b379b6a0f.dmp
01/11/2016  09:53 AM           120,848 217ec146-23e3-4b2c-b8b2-89be8cc3c840.dmp
03/17/2016  10:44 AM           812,928 2e325862-6990-468f-9fe1-4de0729e274c.dmp
01/22/2016  02:11 PM           863,472 39583275-db5c-44f1-b1cc-70be92d1ebed.dmp
01/26/2016  10:59 AM           375,040 3efc4435-c106-4f2f-987a-b2647e1372ce.dmp
01/13/2016  10:22 AM           116,752 41f3df78-4dbe-4483-bdb9-624366b5d439.dmp
01/06/2016  11:02 AM           890,064 46619391-58ad-47e1-a418-1428ea0b88c4.dmp
03/16/2016  11:02 AM           690,496 47096a06-7c02-4268-8fbd-5ee31de4d32c.dmp
03/17/2016  08:50 AM           731,504 490e76ac-3ff7-4c33-a8dc-4b79daccb3c6.dmp
03/16/2016  02:48 PM           657,360 53c3aae4-a37f-406f-9459-00932b8e80b8.dmp
01/18/2016  09:35 AM           120,560 568748bc-660b-43bb-8c85-67dfd80a996d.dmp
01/07/2016  02:36 PM           117,600 59380d05-a5b6-400d-9469-4a209ee07da3.dmp
01/21/2016  10:51 AM           932,448 5aa559a3-5caa-4203-919e-aa1c7c7f8f95.dmp
01/11/2016  09:53 AM           119,184 665e2df6-ca37-4242-a3fe-050e0a3ed375.dmp
03/17/2016  10:16 AM           679,280 68a122f8-0c23-4d6d-a70e-84d30bec85e8.dmp
03/21/2016  09:38 AM           572,848 68fbee01-3515-4b22-943e-1d9b6cded44a.dmp
01/13/2016  10:22 AM           179,088 71ce41be-4fe5-48b1-8ace-f2e367761f2c.dmp
01/13/2016  10:22 AM           120,960 76b5023f-9b00-4cd5-9bf9-84853cc34fca.dmp
01/13/2016  10:22 AM           112,608 77aafad7-a139-48fb-acf6-1acadac82b41.dmp
01/06/2016  11:31 AM           813,568 7a3aa2f2-75b2-4147-a67f-ae82357501c7.dmp
01/25/2016  09:59 AM           900,576 7ead3c64-5e44-4749-8771-fdf21650bdab.dmp
03/16/2016  09:06 AM           702,192 8e43770a-af51-40a9-8c8e-7e750eab5708.dmp
03/16/2016  02:57 PM           708,336 8f16c873-040d-470a-8f41-158c331c2008.dmp
03/21/2016  09:38 AM           514,192 93d18656-99bb-4ae8-9d7c-f5b51dc9b5eb.dmp
01/06/2016  07:47 PM           813,344 9bacb5b5-38be-4eb2-8dfd-824dbd312da4.dmp
01/22/2016  10:51 AM           892,272 9f1308e0-c19b-4151-8ad8-a19255461c0b.dmp
01/07/2016  02:36 PM           116,032 b10e6e23-d606-49c5-b2bc-87d1b4ecfa9e.dmp
03/16/2016  10:42 AM           683,344 b6434050-2a61-47ed-8288-079e800f0d1a.dmp
03/17/2016  09:46 AM           687,744 c6fb0871-534e-4312-a0aa-4520b36e1070.dmp
03/17/2016  10:18 AM           664,352 cec57556-c651-4cb3-ba1d-f060c8262e1e.dmp
03/17/2016  09:25 AM           639,312 d231d4be-7a81-43d0-bcdf-7f8b4c971404.dmp
03/07/2016  09:46 AM           169,824 d2a50524-b0a8-4f2b-a6e7-2f73e3e85e57.dmp
01/22/2016  12:44 PM           936,960 d9e887ca-644d-4abc-a43e-4bfde114f4bf.dmp
03/16/2016  10:55 AM           681,328 da571468-8579-455f-a029-0758119a5a73.dmp
01/18/2016  09:35 AM            87,488 ed03c5e2-ea00-4ea4-833b-5ba2975ccf06.dmp
03/21/2016  09:38 AM           446,592 f42ed34f-5736-4397-a37a-ec174225aedf.dmp
01/06/2016  04:40 PM           772,112 fd28fc18-a0f7-48c6-9281-52a1dc6e5fbe.dmp
              46 File(s)     48,920,160 bytes
               2 Dir(s)  204,012,019,712 bytes free