[Password Manager] Setup experiment to restrict autofilling of sync credential

chrome/browser/password_manager/chrome_password_manager_client.h

Index: chrome/browser/password_manager/chrome_password_manager_client.h
diff --git a/chrome/browser/password_manager/chrome_password_manager_client.h b/chrome/browser/password_manager/chrome_password_manager_client.h
index 203aa420236567ee9de27022a887f25fb8bbf99a..f9674cd524d67e694215e79946e17a92f9a26dfb 100644
--- a/chrome/browser/password_manager/chrome_password_manager_client.h
+++ b/chrome/browser/password_manager/chrome_password_manager_client.h
@@ -40,6 +40,8 @@ class ChromePasswordManagerClient
   // PasswordManagerClient implementation.
   virtual bool IsAutomaticPasswordSavingEnabled() const OVERRIDE;
   virtual bool IsPasswordManagerEnabledForCurrentPage() const OVERRIDE;
+  virtual bool ShouldFilterAutofillResult(
+      const autofill::PasswordForm& form) const OVERRIDE;
   virtual bool IsSyncAccountCredential(
       const std::string& username, const std::string& origin) const OVERRIDE;
   virtual void PromptUserToSavePassword(
@@ -90,9 +92,18 @@ class ChromePasswordManagerClient
   // Returns true if the password manager should be enabled during sync signin.
   static bool EnabledForSyncSignin();
 
- private:
+ protected:
+  // Callable for tests.
   ChromePasswordManagerClient(content::WebContents* web_contents,
                               autofill::AutofillClient* autofill_client);
+
+ private:
+  enum AutofillForSyncCredentialsState {
+    ALLOW_SYNC_CREDENTIALS,
+    DISALLOW_SYNC_CREDENTIALS_FOR_REAUTH,
+    DISALLOW_SYNC_CREDENTIALS,
+  };
+
   friend class content::WebContentsUserData<ChromePasswordManagerClient>;
 
   // content::WebContentsObserver overrides.
@@ -122,6 +133,13 @@ class ChromePasswordManagerClient
   // |can_use_log_router_|.
   void NotifyRendererOfLoggingAvailability();
 
+  // Returns true if the last loaded page was for transactional re-auth on a
+  // Google property.
+  bool LastLoadWasTransactionalReauthPage() const;
+
+  // Sets |autofill_state_| based on experiment and flag values.
+  void SetUpAutofillSyncState();
+
   Profile* const profile_;
 
   password_manager::ContentPasswordManagerDriver driver_;
@@ -139,6 +157,9 @@ class ChromePasswordManagerClient
   // True if |this| is registered with some LogRouter which can accept logs.
   bool can_use_log_router_;
 
+  // How to handle the sync credential in ShouldFilterAutofillResult().
+  AutofillForSyncCredentialsState autofill_sync_state_;
+
   DISALLOW_COPY_AND_ASSIGN(ChromePasswordManagerClient);
 };