TT#70901 selenium: reqire a customer when creating a subscriber

- previously it was possible to create a subscriber without creating a
customer. it would just grab the first customer in the customer list and
create a subscriber there. however, since we delete the entire customer now
instead of just the created subscriber and some customers dont allow to create
a subscriber, this feature will be removed.

Change-Id: Ibc8872ebd6073f8ec531a1e9493f036392df0e56

t/selenium/functions/Collections.py

@@ -95,11 +95,10 @@ def delete_customer(driver, name):
     driver.find_element_by_xpath('//*[@id="dataConfirmOK"]').click()
 
 
-def create_subscriber(driver, customername=None):
+def create_subscriber(driver, customername):
     driver.find_element_by_xpath(
         '//*[@id="main-nav"]//*[contains(text(),"Settings")]').click()
     driver.find_element_by_link_text('Customers').click()
-    if customername:
     Functions.fill_element(
         driver, '//*[@id="Customer_table_filter"]//input',
         'thisshouldnotexist')
@@ -118,15 +117,6 @@ def create_subscriber(driver, customername=None):
         '"Details")]')
     )
     hoverclick.perform()
-    else:
-        hoverclick = ActionChains(driver)
-        hoverclick.move_to_element(driver.find_element_by_xpath(
-            '//*[@id="Customer_table"]//tr[1]'))
-        hoverclick.click(driver.find_element_by_xpath(
-            '//*[@id="Customer_table"]//tr[1]//td//a[contains(text(), '
-            '"Details")]')
-        )
-        hoverclick.perform()
     driver.find_element_by_link_text('Expand Groups').click()
     driver.execute_script(
         'arguments[0].scrollIntoView();',
@@ -151,11 +141,10 @@ def create_subscriber(driver, customername=None):
     driver.find_element_by_xpath('//*[@id="save"]').click()
 
 
-def delete_subscriber(driver, customername=None):
+def delete_subscriber(driver, customername):
     driver.find_element_by_xpath(
         '//*[@id="main-nav"]//*[contains(text(),"Settings")]').click()
     driver.find_element_by_link_text('Customers').click()
-    if customername:
     Functions.fill_element(
         driver, '//*[@id="Customer_table_filter"]//input',
         'thisshouldnotexist')
@@ -174,15 +163,6 @@ def delete_subscriber(driver, customername=None):
         '"Details")]')
     )
     hoverclick.perform()
-    else:
-        hoverclick = ActionChains(driver)
-        hoverclick.move_to_element(driver.find_element_by_xpath(
-            '//*[@id="Customer_table"]//tr[1]'))
-        hoverclick.click(driver.find_element_by_xpath(
-            '//*[@id="Customer_table"]//tr[1]//td//a[contains(text(), '
-            '"Details")]')
-        )
-        hoverclick.perform()
     driver.find_element_by_link_text('Expand Groups').click()
     driver.execute_script(
         'arguments[0].scrollIntoView();',