[Password manager tests automation] Fix "No such frame" error.

In some cases selenium are unable to select frame, which give an
exception and prevents test running. Fix this by explicitly navigating
to desired frame.

BUG=369521
R=vabr@chromium.org

Review URL: https://codereview.chromium.org/1147483003

Cr-Commit-Position: refs/heads/master@{#330491}

components/test/data/password_manager/automated_tests/environment.py

@@ -113,8 +113,7 @@ class Environment:
     time".
     """
 
-    self.driver.get("chrome://settings/clearBrowserData")
-    self.driver.switch_to_frame("settings")
+    self.driver.get("chrome://settings-frame/clearBrowserData")
 
     time_range_selector = "#clear-browser-data-time-period"
     # TODO(vabr): Wait until time_range_selector is displayed instead.
@@ -161,8 +160,7 @@ class Environment:
     # TODO(melandory): We should check why it's off in a first place.
     # TODO(melandory): Investigate, maybe there is no need to enable it that
     # often.
-    self.driver.get("chrome://settings")
-    self.driver.switch_to_frame("settings")
+    self.driver.get("chrome://settings-frame")
     script = "document.getElementById('advanced-settings-expander').click();"
     self.driver.execute_script(script)
     # TODO(vabr): Wait until element is displayed instead.