Rewrite std::string("") to std::string(), Linux edition.

chrome/browser/safe_browsing/client_side_detection_host_unittest.cc

 // Copyright (c) 2012 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 "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/stringprintf.h"
 #include "base/synchronization/waitable_event.h"
 #include "chrome/browser/safe_browsing/browser_feature_extractor.h"
@@ skipping 617 matching lines @@
   SetRedirectChain(redirect_chain);
   OnPhishingDetectionDone(verdict.SerializeAsString());
   MessageLoop::current()->Run();
   EXPECT_TRUE(Mock::VerifyAndClear(csd_service_.get()));
 }
 
 TEST_F(ClientSideDetectionHostTest, UpdateIPHostMap) {
   BrowseInfo* browse_info = GetBrowseInfo();
 
   // Empty IP or host are skipped
-  UpdateIPHostMap("250.10.10.10", "");
+  UpdateIPHostMap("250.10.10.10", std::string());
   ASSERT_EQ(0U, browse_info->ips.size());
-  UpdateIPHostMap("", "google.com/");
+  UpdateIPHostMap(std::string(), "google.com/");
   ASSERT_EQ(0U, browse_info->ips.size());
-  UpdateIPHostMap("", "");
+  UpdateIPHostMap(std::string(), std::string());
   ASSERT_EQ(0U, browse_info->ips.size());
 
   std::set<std::string> expected_hosts;
   for (int i = 0; i < 20; i++) {
     std::string host = base::StringPrintf("%d.com/", i);
     expected_hosts.insert(host);
     UpdateIPHostMap("250.10.10.10", host);
   }
   ASSERT_EQ(1U, browse_info->ips.size());
   ASSERT_EQ(20U, browse_info->ips["250.10.10.10"].size());
@@ skipping 308 matching lines @@
   EXPECT_TRUE(Mock::VerifyAndClear(ui_manager_.get()));
   EXPECT_EQ(url, resource.url);
   EXPECT_EQ(url, resource.original_url);
   resource.callback.Reset();
   msg = process()->sink().GetFirstMessageMatching(
       SafeBrowsingMsg_StartPhishingDetection::ID);
   ASSERT_FALSE(msg);
 }
 
 }  // namespace safe_browsing