Rename Target.writeOutline() into computeOutline(), add separate KernelTarget.writeOutline().

pkg/kernel/test/interpreter/suite.dart

Index: pkg/kernel/test/interpreter/suite.dart
diff --git a/pkg/kernel/test/interpreter/suite.dart b/pkg/kernel/test/interpreter/suite.dart
index 0332f419b94b735c2d2e44e84e5fc3aae17d5b92..2396a1f1c0b845c243ebb362012715f077a4f3cf 100644
--- a/pkg/kernel/test/interpreter/suite.dart
+++ b/pkg/kernel/test/interpreter/suite.dart
@@ -84,8 +84,8 @@ class FastaCompile extends Step<TestDescription, Program, InterpreterContext> {
     Program p;
     try {
       sourceTarget.read(description.uri);
-      await dillTarget.writeOutline(null);
-      await sourceTarget.writeOutline(null);
+      await dillTarget.computeOutline();
+      await sourceTarget.computeOutline();
       p = await sourceTarget.writeProgram(null);
     } on InputError catch (e, s) {
       return fail(null, e.error, s);