Increase test runner speed.

test/cctest/cctest.status

Index: test/cctest/cctest.status
diff --git a/test/cctest/cctest.status b/test/cctest/cctest.status
index a596add43abf8bd5202d3f3abea575a04fbf40ad..e4fe0d849b4eaa06c5ae3812f3020ad95a2d2ce0 100644
--- a/test/cctest/cctest.status
+++ b/test/cctest/cctest.status
@@ -60,6 +60,13 @@
   # running several variants. Note that this still takes ages, because there
   # are actually 13 * 38 * 5 * 128 = 316160 individual tests hidden here.
   'test-parsing/ParserSync': [PASS, NO_VARIANTS],
+
+  ############################################################################
+  # Slow tests.
+  'test-api/Threading1': [PASS, ['mode == debug', SLOW]],
+  'test-api/Threading2': [PASS, ['mode == debug', SLOW]],
+  'test-api/Threading3': [PASS, ['mode == debug', SLOW]],
+  'test-api/Threading4': [PASS, ['mode == debug', SLOW]],
 }],  # ALWAYS
 
 ##############################################################################
@@ -89,6 +96,13 @@
   'test-serialize/DeserializeFromSecondSerializationAndRunScript2': [SKIP],
   'test-serialize/DeserializeAndRunScript2': [SKIP],
   'test-serialize/DeserializeFromSecondSerialization': [SKIP],
+
+  ############################################################################
+  # Slow tests.
+  'test-api/Threading1': [PASS, SLOW],
+  'test-api/Threading2': [PASS, SLOW],
+  'test-api/Threading3': [PASS, SLOW],
+  'test-api/Threading4': [PASS, SLOW],
 }],  # 'arch == arm'
 
 ##############################################################################