Add new scenarios for font changes

There is currently some duplication between the various page objects
and other code. Those should be cleaned up incrementally.

Change-Id: I592829a00ca65bbecd5399b773c885c764c1cc06

tests/browser/features/font_selection.feature

@@ -0,0 +1,38 @@
+@reset-preferences-after @login @en.wikipedia.beta.wmflabs.org @commons.wikimedia.beta.wmflabs.org
+Feature: Font selection
+
+In order to have better using experience,
+As a reader and writer,
+I want to change or disable the fonts for interface and content.
+
+In addition the user is provided live preview feature: changes are applied
+immediately when selection is made. Changes can either be applied or discared
+for easy testing.
+
+Background:
+  Given I am logged in
+    And I set "German" as the interface language
+    And the content language is "English"
+    And I inspect current fonts
+
+Scenario: Discarding live preview of content font
+  When I open "Fonts" panel of language settings
+    And I select "OpenDyslexic" font for the content language for the live preview
+    And I close the panel to discard the changes
+  Then the active content font must be the same as font prior to the preview
+    # System is the default value for English and German
+    And the selected content font must be "system"
+
+Scenario: Discarding live preview of interface font
+  When I open "Fonts" panel of language settings
+    And I select "OpenDyslexic" font for the interface language for the live preview
+    And I close the panel to discard the changes
+  Then the active interface font must be the same as font prior to the preview
+    # System is the default value for English and German
+    And the selected interface font must be "system"
+
+Scenario: Applying the live preview of interface font
+  When I open "Fonts" panel of language settings
+    And I select "OpenDyslexic" font for the interface language for the live preview
+    And I apply the changes
+  Then the interface font must be changed to the "OpenDyslexic" font