Only run mojo_{shell,application_manager,view_manager}_unittests on linux

testing/buildbot/chromium_trybot.json

Index: testing/buildbot/chromium_trybot.json
diff --git a/testing/buildbot/chromium_trybot.json b/testing/buildbot/chromium_trybot.json
index 7f85488855a61c675d60488d84d30684545480ec..b8afe094db97158f08ed3540de36f9c203a3a27a 100644
--- a/testing/buildbot/chromium_trybot.json
+++ b/testing/buildbot/chromium_trybot.json
@@ -98,8 +98,14 @@
     "mojo_public_environment_unittests",
     "mojo_public_system_unittests",
     "mojo_public_utility_unittests",
-    "mojo_application_manager_unittests",
-    "mojo_shell_tests",
+    {
+      "test": "mojo_application_manager_unittests",
+      "platforms": ["linux"]
+    },
+    {
+      "test": "mojo_shell_tests",
+      "platforms": ["linux"]
+    },
     "mojo_system_unittests",
     {
       "test": "nacl_loader_unittests",
@@ -166,7 +172,7 @@
     },
     {
       "test": "mojo_view_manager_unittests",
-      "platforms": ["linux", "win"]
+      "platforms": ["linux"]
     },
     {
       "test": "views_unittests",