[test] Migrate test configs for main console

This migrates the test configurations of all builders on the main
console (aka client.v8) to the V8 repository, preparing removal from
build/scripts/slave/recipe_modules/v8/builders.py.

NOTRY=true

Bug: chromium:830557
Change-Id: I40b8f31ab48426c7122c87e0221d6f05dc205e81
Reviewed-on: https://chromium-review.googlesource.com/c/1273237
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56547}

infra/testing/PRESUBMIT.py

@@ -115,9 +115,9 @@ def _check_test(error_msg, test):
   if not all(isinstance(x, basestring) for x in test_args):
     errors += error_msg('If specified, all test_args must be strings')
 
-  # Limit shards to 10 to avoid erroneous resource exhaustion.
+  # Limit shards to 12 to avoid erroneous resource exhaustion.
   errors += _check_int_range(
-      error_msg, test, 'shards', lower_bound=1, upper_bound=10)
+      error_msg, test, 'shards', lower_bound=1, upper_bound=12)
 
   variant = test.get('variant', 'default')
   if not variant or not isinstance(variant, basestring):