Fix typo.

tools/telemetry/telemetry/core/backends/chrome/cros_browser_backend.py

Index: tools/telemetry/telemetry/core/backends/chrome/cros_browser_backend.py
diff --git a/tools/telemetry/telemetry/core/backends/chrome/cros_browser_backend.py b/tools/telemetry/telemetry/core/backends/chrome/cros_browser_backend.py
index 364c184f7b898590875128d75caffb49fe9ce80a..81e3c4c8eecdc751a6f14adef2bc2a8e0583f9b6 100644
--- a/tools/telemetry/telemetry/core/backends/chrome/cros_browser_backend.py
+++ b/tools/telemetry/telemetry/core/backends/chrome/cros_browser_backend.py
@@ -336,7 +336,7 @@ class CrOSBrowserBackend(chrome_browser_backend.ChromeBrowserBackend):
         if startup_window_ext_id in self.extension_dict_backend
         else self.tab_list_backend.Get(0, None))
 
-  def _WaitForSigininScreen(self):
+  def _WaitForSigninScreen(self):
     """Waits for oobe to be on the signin or account picker screen."""
     def OnAccountPickerScreen():
       signin_state = self._SigninUIState()
@@ -371,7 +371,7 @@ class CrOSBrowserBackend(chrome_browser_backend.ChromeBrowserBackend):
   def _NavigateGuestLogin(self):
     """Navigates through oobe login screen as guest"""
     assert self.oobe
-    self._WaitForSigininScreen()
+    self._WaitForSigninScreen()
     self._ClickBrowseAsGuest()
     self._WaitForGuestFsMounted()