Bug 1388627 - close_chrome_window always operates in chrome context. r=automatedtester

MozReview-Commit-ID: J1R407tTuy4

--HG--
extra : rebase_source : bd508f1d3dcdfe08580e3dca4c4a64ac507efa92

testing/marionette/harness/marionette_harness/runner/mixins/window_manager.py

@@ -51,12 +51,11 @@ class WindowManagerMixin(object):
             self.start_window = current_chrome_window_handles[0]
         current_chrome_window_handles.remove(self.start_window)
 
-        with self.marionette.using_context("chrome"):
-            for handle in current_chrome_window_handles:
-                self.marionette.switch_to_window(handle)
-                self.marionette.close_chrome_window()
+        for handle in current_chrome_window_handles:
+            self.marionette.switch_to_window(handle)
+            self.marionette.close_chrome_window()
 
-            self.marionette.switch_to_window(self.start_window)
+        self.marionette.switch_to_window(self.start_window)
 
     def open_tab(self, trigger="menu"):
         current_tabs = self.marionette.window_handles