[test] Migrate testing code serializer

This adds testing configs to the V8 side, so that they can be deleted on the
infra side in a follow up.

TBR=yangguo@chromium.org
NOTRY=true

Bug: v8:7302
Change-Id: I93e65576b9799675ea0a8beca188c84a30695de3
Reviewed-on: https://chromium-review.googlesource.com/867037Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50597}

infra/testing/client.v8.pyl

@@ -11,6 +11,15 @@
   #   {'name': 'benchmarks', 'variant': 'default', 'shards': 1},
   # ],
 
+  'V8 Linux - debug ': [
+    {'name': 'd8testing', 'variant': 'code_serializer', 'shards': 1},
+    {'name': 'mozilla', 'variant': 'code_serializer', 'shards': 1},
+    {'name': 'test262_variants', 'variant': 'code_serializer', 'shards': 1},
+    {'name': 'benchmarks', 'variant': 'code_serializer', 'shards': 1},
+  ],
+  'V8 Linux - gc stress': [
+    {'name': 'mjsunit', 'variant': 'slow_path', 'shards': 2},
+  ],
   'V8 Linux64': [
     {'name': 'v8testing', 'variant': 'minor_mc', 'shards': 1},
   ],
@@ -18,9 +27,6 @@
     {'name': 'v8testing', 'variant': 'minor_mc', 'shards': 1},
     {'name': 'v8testing', 'variant': 'slow_path', 'shards': 1},
   ],
-  'V8 Linux - gc stress': [
-    {'name': 'mjsunit', 'variant': 'slow_path', 'shards': 2},
-  ],
   'V8 Linux64 ASAN': [
     {'name': 'v8testing', 'variant': 'slow_path', 'shards': 1},
   ],