rename generation test names to be more descriptive

test/fixtures/generation/harmony-edgecase/export-default-declaration/actual.js

@@ -0,0 +1,3 @@
+export default function a () { }
+// export default var i = 20;
+// export default const K = 20;

test/fixtures/generation/harmony-edgecase/export-default-declaration/expected.js

@@ -0,0 +1,2 @@
+export default function a() {
+}