[chromedriver] setting browser default download directory

chrome/test/chromedriver/client/chromedriver.py

Index: chrome/test/chromedriver/client/chromedriver.py
diff --git a/chrome/test/chromedriver/client/chromedriver.py b/chrome/test/chromedriver/client/chromedriver.py
index fb1aa2b27fded702a22419ca0273bc43a79de2d2..2d5a89a3bfbad070c3e14ccff55ed21edd338e35 100644
--- a/chrome/test/chromedriver/client/chromedriver.py
+++ b/chrome/test/chromedriver/client/chromedriver.py
@@ -66,7 +66,7 @@ class ChromeDriver(object):
                chrome_extensions=None, chrome_log_path=None,
                debugger_address=None, browser_log_level=None,
                performance_log_level=None, mobile_emulation=None,
-               experimental_options=None):
+               experimental_options=None, download_dir=None):
     self._executor = command_executor.CommandExecutor(server_url)
 
     options = {}
@@ -115,6 +115,14 @@ class ChromeDriver(object):
       assert performance_log_level in log_levels
       logging_prefs['performance'] = performance_log_level
 
+    download_prefs = {}
+    if download_dir:
+      if 'prefs' not in options:
+        options['prefs'] = {}
+      if 'download' not in options['prefs']:
+        options['prefs']['download'] = {}
+      options['prefs']['download']['default_directory'] = download_dir
+
     params = {
       'desiredCapabilities': {
         'chromeOptions': options,