Add transport security state generator tests.

net/tools/transport_security_state_generator/preloaded_state_generator.h

Index: net/tools/transport_security_state_generator/preloaded_state_generator.h
diff --git a/net/tools/transport_security_state_generator/preloaded_state_generator.h b/net/tools/transport_security_state_generator/preloaded_state_generator.h
index 562c4f38ead297ff708d356b45a4399568cb1dad..f3626ad0736b6fc0b9b1acd4135798e2be7d04a5 100644
--- a/net/tools/transport_security_state_generator/preloaded_state_generator.h
+++ b/net/tools/transport_security_state_generator/preloaded_state_generator.h
@@ -28,11 +28,11 @@ class PreloadedStateGenerator {
   PreloadedStateGenerator();
   ~PreloadedStateGenerator();
 
-  std::string Generate(const std::string& preload_template,
-                       const TransportSecurityStateEntries& entries,
-                       const DomainIDList& domain_ids,
-                       const Pinsets& pinsets,
-                       bool verbose);
+  bool Generate(const std::string& preload_template,
+                const TransportSecurityStateEntries& entries,
+                const DomainIDList& domain_ids,
+                const Pinsets& pinsets,
+                std::string* output);
 
  private:
   // TODO(Martijnc): Remove the domain IDs from the preload format.