Use kernel to compile tests (#4795)

dart_test.yaml

diff --git a/dart_test.yaml b/dart_test.yaml
index 88b7135..dcc869f 100644
--- a/dart_test.yaml
+++ b/dart_test.yaml
@@ -1,11 +1,11 @@
 platforms:
-  - chrome
   - vm
+  - chrome
 # TODO: Consider testing on Firefox
 
 compilers:
+ - kernel
  - dart2wasm
- - source
  - dart2js
 
 presets: