[Chromedriver] Ensure baseURL is 'about:blank' for dummy page on Chrome 60+.

From Chrome 60 onwards, root.baseURL will no longer be empty and will always return 'about:blank'.
See crbug/711562 for more details.

BUG=chromedriver:1775

Review-Url: https://codereview.chromium.org/2830903005
Cr-Commit-Position: refs/heads/master@{#467328}

chrome/test/chromedriver/chrome/navigation_tracker.cc

@@ -117,15 +117,26 @@ Status NavigationTracker::IsPendingNavigation(const std::string& frame_id,
   if (loading_state_ == kUnknown) {
     // In the case that a http request is sent to server to fetch the page
     // content and the server hasn't responded at all, a dummy page is created
-    // for the new window. In such case, the baseURL will be empty.
+    // for the new window. In such case, the baseURL will be empty for <=M59 ;
+    // whereas the baseURL will be 'about:blank' for >=M60. See crbug/711562.
+    // TODO(gmanikpure):Remove condition for <3076 when we stop supporting M59.
     base::DictionaryValue empty_params;
     std::unique_ptr<base::DictionaryValue> result;
     Status status = client_->SendCommandAndGetResultWithTimeout(
         "DOM.getDocument", empty_params, timeout, &result);
     std::string base_url;
-    if (status.IsError() || !result->GetString("root.baseURL", &base_url))
+    std::string doc_url;
+    if (status.IsError() || !result->GetString("root.baseURL", &base_url) ||
+        !result->GetString("root.documentURL", &doc_url))
       return MakeNavigationCheckFailedStatus(status);
-    if (base_url.empty()) {
+
+    bool condition;
+    if (browser_info_->build_no >= 3076)
+      condition = doc_url != "about:blank" && base_url == "about:blank";
+    else
+      condition = base_url.empty();
+
+    if (condition) {
       *is_pending = true;
       loading_state_ = kLoading;
       return Status(kOk);

chrome/test/chromedriver/chrome/navigation_tracker_unittest.cc

@@ -46,10 +46,13 @@ class DeterminingLoadStateDevToolsClient : public StubDevToolsClient {
       std::unique_ptr<base::DictionaryValue>* result) override {
     if (method == "DOM.getDocument") {
       base::DictionaryValue result_dict;
-      if (has_empty_base_url_)
-        result_dict.SetString("root.baseURL", std::string());
-      else
+      if (has_empty_base_url_) {
+        result_dict.SetString("root.baseURL", "about:blank");
+        result_dict.SetString("root.documentURL", "http://test");
+      } else {
         result_dict.SetString("root.baseURL", "http://test");
+        result_dict.SetString("root.documentURL", "http://test");
+      }
       result->reset(result_dict.DeepCopy());
       return Status(kOk);
     } else if (method == "Runtime.evaluate") {

chrome/test/chromedriver/test/run_py_tests.py

@@ -73,8 +73,6 @@ _NEGATIVE_FILTER = [
 
 _VERSION_SPECIFIC_FILTER = {}
 _VERSION_SPECIFIC_FILTER['HEAD'] = [
-    # https://bugs.chromium.org/p/chromedriver/issues/detail?id=1775
-    'ChromeDriverTest.testShouldHandleNewWindowLoadingProperly',
 ]
 _VERSION_SPECIFIC_FILTER['58'] = [
     # https://bugs.chromium.org/p/chromedriver/issues/detail?id=1673