Align Send Alert Text with Element Send Keys

The WebDriver specification has been updated to align Send Alert Text
and Element Send Keys so they both send the same key and value structure
simplifying send keys between the two.

py/selenium/webdriver/common/alert.py

@@ -19,6 +19,7 @@
 The Alert implementation.
 """
 
+from selenium.webdriver.common.utils import keys_to_typing
 from selenium.webdriver.remote.command import Command
 
 
@@ -88,7 +89,10 @@ def send_keys(self, keysToSend):
 
 
         """
-        self.driver.execute(Command.SET_ALERT_VALUE, {'text': keysToSend})
+        if self.driver.w3c:
+            self.driver.execute(Command.SET_ALERT_VALUE, {'value': keys_to_typing(keysToSend)})
+        else:
+            self.driver.execute(Command.SET_ALERT_VALUE, {'text': keysToSend})
 
     def authenticate(self, username, password):
         """