[chromedriver] Support clicking an element in sub frames.

chrome/test/chromedriver/element_commands.cc

Index: chrome/test/chromedriver/element_commands.cc
diff --git a/chrome/test/chromedriver/element_commands.cc b/chrome/test/chromedriver/element_commands.cc
index 9637054ab1e6410510452c462fe166135b5b94a1..1911533483ab6c488fe08c75ded5bfa2629ab79f 100644
--- a/chrome/test/chromedriver/element_commands.cc
+++ b/chrome/test/chromedriver/element_commands.cc
@@ -124,7 +124,7 @@ Status ExecuteHoverOverElement(
     scoped_ptr<base::Value>* value) {
   WebPoint location;
   Status status = GetElementClickableLocation(
-      session, web_view, element_id, &location, NULL);
+      session, web_view, element_id, &location);
   if (status.IsError())
     return status;
 
@@ -160,13 +160,10 @@ Status ExecuteClickElement(
       return SetOptionElementSelected(session, web_view, element_id, true);
   } else {
     WebPoint location;
-    bool is_clickable;
     status = GetElementClickableLocation(
-        session, web_view, element_id, &location, &is_clickable);
+        session, web_view, element_id, &location);
     if (status.IsError())
       return status;
-    if (!is_clickable)
-      return Status(kUnknownError, status.message());
 
     std::list<MouseEvent> events;
     events.push_back(