Double shard dbg builds of net_unittests on linux(-chromos) testers.

Bug: 851996
Change-Id: Id1b01007c65fe417dc9f3beac1aac158e5c97bd0
Reviewed-on: https://chromium-review.googlesource.com/1097701
Reviewed-by: John Budorick <[email protected]>
Reviewed-by: Dirk Pranke <[email protected]>
Cr-Commit-Position: refs/heads/master@{#566712}
diff --git a/testing/buildbot/test_suite_exceptions.pyl b/testing/buildbot/test_suite_exceptions.pyl
index d43e076..0edee15 100644
--- a/testing/buildbot/test_suite_exceptions.pyl
+++ b/testing/buildbot/test_suite_exceptions.pyl
@@ -1754,6 +1754,22 @@
           'shards': 4,
         }
       },
+      # The suite runs signficantly slower on linux dbg, so increase shards.
+      'Linux Tests (dbg)(1)': {
+        'swarming': {
+          'shards': 2,
+        },
+      },
+      'Linux Tests (dbg)(1)(32)': {
+        'swarming': {
+          'shards': 2,
+        },
+      },
+      'linux-chromeos-dbg': {
+        'swarming': {
+          'shards': 2,
+        },
+      },
     },
   },
   'network_service_browser_tests': {