Add a unittest for PasswordAutofillAgent

components/autofill/content/renderer/password_autofill_agent.h

Index: components/autofill/content/renderer/password_autofill_agent.h
diff --git a/components/autofill/content/renderer/password_autofill_agent.h b/components/autofill/content/renderer/password_autofill_agent.h
index 24a7aa9099f7f7e37200b66cc1db11d9f4b64e14..0436b270ad022c058343a23415c6bb0793b95050 100644
--- a/components/autofill/content/renderer/password_autofill_agent.h
+++ b/components/autofill/content/renderer/password_autofill_agent.h
@@ -27,6 +27,7 @@ namespace autofill {
 // There is one PasswordAutofillAgent per RenderView.
 class PasswordAutofillAgent : public content::RenderViewObserver {
  public:
+  // In unit tests, |render_view| can be NULL.
   explicit PasswordAutofillAgent(content::RenderView* render_view);
   virtual ~PasswordAutofillAgent();
 
@@ -64,6 +65,9 @@ class PasswordAutofillAgent : public content::RenderViewObserver {
   virtual bool OriginCanAccessPasswordManager(
       const blink::WebSecurityOrigin& origin);
 
+  // Only for tests.
+  bool logging_state_active() { return logging_state_active_; }
+
  private:
   friend class PasswordAutofillAgentTest;