Add a test for toggling logging in PasswordAutofillAgent

chrome/renderer/autofill/password_autofill_agent_browsertest.cc

Index: chrome/renderer/autofill/password_autofill_agent_browsertest.cc
diff --git a/chrome/renderer/autofill/password_autofill_agent_browsertest.cc b/chrome/renderer/autofill/password_autofill_agent_browsertest.cc
index 955156d58985b17bf0e878badcc60d89eaed3bb4..5bc1c941d26e469aefc343e0b1a6caf30faee9c6 100644
--- a/chrome/renderer/autofill/password_autofill_agent_browsertest.cc
+++ b/chrome/renderer/autofill/password_autofill_agent_browsertest.cc
@@ -1047,4 +1047,24 @@ TEST_F(PasswordAutofillAgentTest, AcceptSuggestion) {
   CheckTextFieldsDOMState(kBobUsername, true, kCarolPassword, true);
 }
 
+// Tests that the PasswordAutofillAgent reacts appropriately to messages about
+// changing the logging state.
+// Note: this seems like better suited for a unit test, but for technical
+// complications was done as a browser test, see the discussion at
+// https://codereview.chromium.org/258473005/.
+TEST_F(PasswordAutofillAgentTest, OnChangeLoggingState) {
+  // Up-cast to access OnMessageReceived, which is private in the agent.
+  IPC::Listener* const agent_listener(password_autofill_);
+
+  EXPECT_FALSE(password_autofill_->logging_state_active());
+
+  AutofillMsg_ChangeLoggingState msg_activate(0, true);
+  EXPECT_TRUE(agent_listener->OnMessageReceived(msg_activate));
+  EXPECT_TRUE(password_autofill_->logging_state_active());
+
+  AutofillMsg_ChangeLoggingState msg_deactivate(0, false);
+  EXPECT_TRUE(agent_listener->OnMessageReceived(msg_deactivate));
+  EXPECT_FALSE(password_autofill_->logging_state_active());
+}

[Ilya Sherman, 2014/04/25 18:25:29]

Hmm, could you instead test that RPCs are or aren't sent, depending on the
logging status?  Conceivably, the code could correctly set
|logging_state_active_|, but then incorrectly read from it.  It's generally most
useful to test externally observable behavior, rather than internal class
details.

[vabr (Chromium), 2014/04/28 14:31:09]

Absolutely, that's a very good point.
Done.

+
 }  // namespace autofill