[Password Manager] Add UMA stats to track interaction with synced accounts.

components/password_manager/core/browser/password_manager_client.h

Index: components/password_manager/core/browser/password_manager_client.h
diff --git a/components/password_manager/core/browser/password_manager_client.h b/components/password_manager/core/browser/password_manager_client.h
index e1c765e4507554816cc5d0807f9f96572f568ca6..782c20ef3c88cba6e6335ff70bf8af8b2967c6fd 100644
--- a/components/password_manager/core/browser/password_manager_client.h
+++ b/components/password_manager/core/browser/password_manager_client.h
@@ -30,6 +30,11 @@ class PasswordManagerClient {
   // The default return value is false.
   virtual bool IsAutomaticPasswordSavingEnabled() const;
 
+  // Returns true if |username| and |origin| correspond to the account which is
+  // syncing passwords.
+  virtual bool IsPasswordSyncAccountCredential(
+      const std::string& username, const std::string& origin) const = 0;
+
   // Informs the embedder of a password form that can be saved if the user
   // allows it. The embedder is not required to prompt the user if it decides
   // that this form doesn't need to be saved.