Run native_theme unittests everywhere we run views_unittests.

testing/buildbot/chromium.chromiumos.json

Index: testing/buildbot/chromium.chromiumos.json
diff --git a/testing/buildbot/chromium.chromiumos.json b/testing/buildbot/chromium.chromiumos.json
index b67066989e4e289ca6e7a172d1d53f454e0f5de8..e866409317a24df9159dedf4418e13971afbee13 100644
--- a/testing/buildbot/chromium.chromiumos.json
+++ b/testing/buildbot/chromium.chromiumos.json
@@ -285,6 +285,12 @@
         "swarming": {
           "can_use_on_swarming_builders": true
         },
+        "test": "native_theme_unittests"
+      },
+      {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "net_unittests"
       },
       {
@@ -710,6 +716,12 @@
         "swarming": {
           "can_use_on_swarming_builders": true
         },
+        "test": "native_theme_unittests"
+      },
+      {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "net_unittests"
       },
       {
@@ -1056,6 +1068,12 @@
         "swarming": {
           "can_use_on_swarming_builders": true
         },
+        "test": "native_theme_unittests"
+      },
+      {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "net_unittests"
       },
       {