[ChromeDriver] Send DOM.getDocument after each DOM.documentUpdated.

chrome/test/chromedriver/frame_tracker.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/test/chromedriver/frame_tracker.h"
 
 #include <utility>
 
 #include "base/json/json_writer.h"
 #include "base/logging.h"
 #include "base/values.h"
+#include "chrome/test/chromedriver/devtools_client.h"
 #include "chrome/test/chromedriver/status.h"
 
 FrameTracker::FrameTracker() {}
 
 FrameTracker::~FrameTracker() {}
 
+Status FrameTracker::Init(DevToolsClient* client) {
+  // Enable runtime events to allow tracking execution context creation.
+  base::DictionaryValue params;
+  DCHECK(client);
+  return client->SendCommand("Runtime.enable", params);
+}
+
 Status FrameTracker::GetFrameForContextId(
     int context_id, std::string* frame_id) {
   if (context_to_frame_map_.count(context_id) == 0)
     return Status(kUnknownError, "execution context does not have a frame");
   *frame_id = context_to_frame_map_[context_id];
   return Status(kOk);
 }
 
 Status FrameTracker::GetContextIdForFrame(
     const std::string& frame_id, int* context_id) {
@@ skipping 21 matching lines @@
                  << json;
       return;
     }
     frame_to_context_map_.insert(std::make_pair(frame_id, context_id));
     context_to_frame_map_.insert(std::make_pair(context_id, frame_id));
   } else if (method == "DOM.documentUpdated") {
     frame_to_context_map_.clear();
     context_to_frame_map_.clear();
   }
 }