Reland "[ChromeDriver] Making CloseWindow W3C Compliant"

This is a reland of be44dc6b

Original change's description:
> [ChromeDriver] Making CloseWindow W3C Compliant
> 
> Making CloseWindow W3C compliant by returning the result of
> GetWindowHandles. Modified testCloseWindow in run_py_tests.py
> to test this conformance.
> 
> Bug: chromedriver:1990
> Change-Id: I2e90e9e9ca16559ea3678846a7d605b402b4d431
> Reviewed-on: https://chromium-review.googlesource.com/1115813
> Reviewed-by: Caleb Rouleau <crouleau@chromium.org>
> Reviewed-by: John Chen <johnchen@chromium.org>
> Commit-Queue: Cole Winstanley <cwinstanley@google.com>
> Cr-Commit-Position: refs/heads/master@{#571334}

Bug: chromedriver:1990
Change-Id: Iac9b60f09aeb697151077410dbcb408dbba420c2
Reviewed-on: https://chromium-review.googlesource.com/1120696Reviewed-by: John Chen <johnchen@chromium.org>
Commit-Queue: Cole Winstanley <cwinstanley@google.com>
Cr-Commit-Position: refs/heads/master@{#571639}

chrome/test/chromedriver/client/chromedriver.py

@@ -308,7 +308,7 @@ class ChromeDriver(object):
     return self.ExecuteCommand(Command.GET_CURRENT_WINDOW_HANDLE)
 
   def CloseWindow(self):
-    self.ExecuteCommand(Command.CLOSE)
+    return self.ExecuteCommand(Command.CLOSE)
 
   def Load(self, url):
     self.ExecuteCommand(Command.GET, {'url': url})

chrome/test/chromedriver/session_commands.cc

@@ -414,11 +414,10 @@ Status ExecuteClose(Session* session,
   if (status.IsError())
     return status;
 
-  status = session->chrome->GetWebViewIds(&web_view_ids,
-                                          session->w3c_compliant);
+  status = ExecuteGetWindowHandles(session, base::DictionaryValue(), value);
   if ((status.code() == kChromeNotReachable && is_last_web_view) ||
-      (status.IsOk() && web_view_ids.empty())) {
-    // If no window is open, close is the equivalent of calling "quit".
+      (status.IsOk() && (*value)->GetList().empty())) {
+    // If the only open window was closed, close is the same as calling "quit".
     session->quit = true;
     return session->chrome->Quit();
   }

chrome/test/chromedriver/test/run_py_tests.py

@@ -388,16 +388,21 @@ class ChromeDriverTest(ChromeDriverBaseTestWithWebServer):
     self.assertEquals(new_window_handle, self._driver.GetCurrentWindowHandle())
     self.assertRaises(chromedriver.NoSuchElement,
                       self._driver.FindElement, 'id', 'link')
-    self._driver.CloseWindow()
+    close_returned_handles = self._driver.CloseWindow()
     self.assertRaises(chromedriver.NoSuchWindow,
                       self._driver.GetCurrentWindowHandle)
     new_handles = self._driver.GetWindowHandles()
+    self.assertEquals(close_returned_handles, new_handles)
     for old_handle in old_handles:
       self.assertTrue(old_handle in new_handles)
     for handle in new_handles:
       self._driver.SwitchToWindow(handle)
       self.assertEquals(handle, self._driver.GetCurrentWindowHandle())
-      self._driver.CloseWindow()
+      close_handles = self._driver.CloseWindow()
+      # CloseWindow quits the session if on the last window.
+      if handle is not new_handles[-1]:
+        from_get_window_handles = self._driver.GetWindowHandles()
+        self.assertEquals(close_handles, from_get_window_handles)
 
   def testCloseWindowUsingJavascript(self):
     self._driver.Load(self.GetHttpUrlForFile('/chromedriver/page_test.html'))