Added a new automation hook ExecuteJavascriptInOOBEWebUI() to execute javascript prior to login on…

chrome/test/pyautolib/pyauto.py

Index: chrome/test/pyautolib/pyauto.py
diff --git a/chrome/test/pyautolib/pyauto.py b/chrome/test/pyautolib/pyauto.py
index 683b8a4c75effebee230a7bde1a33ceafed2d139..78a10a94d56cee1cbe7cac73e6dbdfa2957c9c8f 100755
--- a/chrome/test/pyautolib/pyauto.py
+++ b/chrome/test/pyautolib/pyauto.py
@@ -3213,6 +3213,36 @@ class PyUITest(pyautolib.PyUITestBase, unittest.TestCase):
     json_string = '[' + result + ']'
     return json.loads(json_string)[0]
 
+  def ExecuteJavascriptInLoginWebUI(self, js, frame_xpath=''):
+    """Executes a script in the specified frame of a pre-login WebUI.
+
+    By default, execute the script in the top frame of the login window. This
+    also works for other pre-login pages, including the enterprise enrollment
+    screen. The invoked javascript function must send a result back via the
+    domAutomationController.send function, or this function will never return.
+
+    Args:
+      js: Script to be executed.
+      frame_xpath: XPath of the frame to execute the script. Default is no
+          frame. Example: '//frames[1]'
+
+    Returns:
+      A value that was sent back via the domAutomationController.send method.
+
+    Raises:
+      pyauto_errors.JSONInterfaceError if the automation call returns an error.
+    """
+    cmd_dict = {
+      'command': 'ExecuteJavascriptInLoginWebUI',
+      'javascript': js,
+      'frame_xpath': frame_xpath,
+    }
+    result = self._GetResultFromJSONRequest(cmd_dict, windex=None)['result']
+    # Wrap result in an array before deserializing because valid JSON has an
+    # array or an object as the root.
+    return json.loads('[' + result + ']')[0]
+
+
   def GetDOMValue(self, expr, tab_index=0, windex=0, frame_xpath=''):
     """Executes a Javascript expression and returns the value.