Add password manager autocomplete suggestion when a username element in clicked.

components/autofill/content/renderer/test_password_autofill_agent.h

Index: components/autofill/content/renderer/test_password_autofill_agent.h
diff --git a/components/autofill/content/renderer/test_password_autofill_agent.h b/components/autofill/content/renderer/test_password_autofill_agent.h
index 01f5a4b07387e444cc571f07d77320a95c581348..cbd73592989698296c428211ccad164ff9145eec 100644
--- a/components/autofill/content/renderer/test_password_autofill_agent.h
+++ b/components/autofill/content/renderer/test_password_autofill_agent.h
@@ -5,7 +5,11 @@
 #ifndef COMPONENTS_AUTOFILL_CONTENT_RENDERER_TEST_PASSWORD_AUTOFILL_AGENT_H_
 #define COMPONENTS_AUTOFILL_CONTENT_RENDERER_TEST_PASSWORD_AUTOFILL_AGENT_H_
 
+#include <vector>
+
+#include "base/memory/scoped_vector.h"
 #include "components/autofill/content/renderer/password_autofill_agent.h"
+#include "ipc/ipc_message.h"
 
 namespace autofill {
 
@@ -14,12 +18,30 @@ class TestPasswordAutofillAgent : public PasswordAutofillAgent {
   explicit TestPasswordAutofillAgent(content::RenderView* render_view);
   virtual ~TestPasswordAutofillAgent();
 
+  // content::RenderViewObserver implementation:
+  virtual bool Send(IPC::Message* message) OVERRIDE;
+
+  // Access messages that would have been sent to the browser.
+  const std::vector<IPC::Message*>& messages() const { return messages_.get(); }
+
+  // Enqueue messages and do not forward them.
+  void pause_messages() { pause_messages_ = true; }
+
+  // Stop enqueuing messages and forward on all received messages.
+  void resume_messages();
+
+  void clear_messages() { messages_.clear(); }
+
  private:
   // Always returns true. This allows browser tests with "data: " URL scheme to
   // work with the password manager.
   // PasswordAutofillAgent:
   virtual bool OriginCanAccessPasswordManager(
       const blink::WebSecurityOrigin& origin) OVERRIDE;
+
+  ScopedVector<IPC::Message> messages_;
+
+  bool pause_messages_;
 };
 
 }  // namespace autofill