[ChromeDriver] Fix ClickScrollingTests on Mac

Update ScrollElementRegionIntoViewHelper() to look for
kElementClickIntercepted instead of kUnknownError.
Reason was in https://crrev.com/634697 which changed
VerifyElementClickable() function to return
kElementClickIntercepted instead of kUnknownError.

Bug: chromedriver:2856
Change-Id: Ic2eee972663df9163e6fa6c56adcca1512e14efc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1797706Reviewed-by: John Chen <johnchen@chromium.org>
Commit-Queue: Tatiana Buldina <buldina@chromium.org>
Cr-Commit-Position: refs/heads/master@{#695775}

chrome/test/chromedriver/element_util.cc

@@ -18,6 +18,7 @@
 #include "chrome/test/chromedriver/chrome/js.h"
 #include "chrome/test/chromedriver/chrome/status.h"
 #include "chrome/test/chromedriver/chrome/web_view.h"
+#include "chrome/test/chromedriver/net/timeout.h"
 #include "chrome/test/chromedriver/session.h"
 #include "third_party/webdriver/atoms.h"
 
@@ -157,8 +158,7 @@ Status ScrollElementRegionIntoViewHelper(
     middle.Offset(region.Width() / 2, region.Height() / 2);
     status = VerifyElementClickable(
         frame, web_view, clickable_element_id, middle);
-    if (status.code() == kUnknownError &&
-        status.message().find("is not clickable") != std::string::npos) {
+    if (status.code() == kElementClickIntercepted) {
       // Clicking at the target location isn't reaching the target element.
       // One possible cause is a scroll event handler has shifted the element.
       // Try again to get the updated location of the target element.
@@ -174,8 +174,15 @@ Status ScrollElementRegionIntoViewHelper(
       }
       middle = tmp_location;
       middle.Offset(region.Width() / 2, region.Height() / 2);
+      Timeout response_timeout(base::TimeDelta::FromSeconds(1));
+      do {
         status =
          VerifyElementClickable(frame, web_view, clickable_element_id, middle);
+        if (status.code() == kElementClickIntercepted)
+          base::PlatformThread::Sleep(base::TimeDelta::FromMilliseconds(50));
+        else
+          break;
+      } while (!response_timeout.IsExpired());
     }
     if (status.IsError())
       return status;

chrome/test/chromedriver/test/test_expectations

@@ -48,10 +48,6 @@ _OS_NEGATIVE_FILTER['mac'] = [
     # Test 'WindowTest.testSetsTheSizeOfTheCurrentWindowFromIframe' passes while it is run
     # standalone and fails in a test suit run
     'WindowTest.testSetsTheSizeOfTheCurrentWindowFromIframe',
-
-    # https://bugs.chromium.org/p/chromedriver/issues/detail?id=2856
-    'ClickScrollingTest.testShouldBeAbleToClickElementThatIsOutOfViewInANestedFrameThatIsOutOfView',
-    'ClickScrollingTest.testShouldBeAbleToClickElementThatIsOutOfViewInANestedFrame',
 ]
 
 _OS_NEGATIVE_FILTER['android:chrome'] = [