Create LoadingDataCollector class and have observers rely on it instead of ResourcePrefetchPredictor

chrome/browser/predictors/resource_prefetcher_unittest.cc

 // Copyright 2014 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/browser/predictors/resource_prefetcher.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <string>
 #include <utility>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/message_loop/message_loop.h"
 #include "base/test/histogram_tester.h"
-#include "chrome/browser/predictors/resource_prefetch_predictor_test_util.h"
+#include "chrome/browser/predictors/loading_test_util.h"
 #include "chrome/browser/predictors/resource_prefetcher_manager.h"
 #include "chrome/test/base/testing_profile.h"
 #include "content/public/test/test_browser_thread.h"
 #include "net/base/load_flags.h"
 #include "net/url_request/redirect_info.h"
 #include "net/url_request/url_request.h"
 #include "net/url_request/url_request_test_util.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 338 matching lines @@
 
   OnResponse(https_resource);
   OnResponse(http_resource);
 
   // Expect the final call.
   EXPECT_TRUE(
       prefetcher_delegate_.ResourcePrefetcherFinishedCalled(prefetcher_.get()));
 }
 
 }  // namespace predictors