wire: respect -record flag for tests (google/go-cloud#282)

Fixes google/go-cloud#281

internal/wire/testdata/InjectWithPanic/want/wire_gen.go

@@ -0,0 +1,13 @@
+// Code generated by Wire. DO NOT EDIT.
+
+//go:generate wire
+//+build !wireinject
+
+package main
+
+// Injectors from wire.go:
+
+func injectedMessage() string {
+	string2 := provideMessage()
+	return string2
+}