Make SplitStringUsingSubstr have consistent args.

chrome/browser/metrics/perf/perf_provider_chromeos.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 "chrome/browser/metrics/perf/perf_provider_chromeos.h"
 
 #include <stddef.h>
 #include <algorithm>
 #include <map>
 #include <string>
@@ skipping 80 matching lines @@
   // NB: StringToInt64 will set value even if the conversion fails.
   if (!base::StringToInt64(it->second, &value))
     return false;
   *out = value;
   return true;
 }
 
 // Parses the key. e.g.: "PerfCommand::arm::0" returns "arm"
 bool ExtractPerfCommandCpuSpecifier(const std::string& key,
                                     std::string* cpu_specifier) {
-  std::vector<std::string> tokens;
-  base::SplitStringUsingSubstr(key, "::", &tokens);
+  std::vector<std::string> tokens = base::SplitStringUsingSubstr(
+      key, "::", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
   if (tokens.size() != 3)
     return false;
   if (tokens[0] != "PerfCommand")
     return false;
   *cpu_specifier = tokens[1];
   // tokens[2] is just a unique string (usually an index).
   return true;
 }
 
 // Hopefully we never need a space in a command argument.
@@ skipping 549 matching lines @@
   std::unique_ptr<SampledProfile> sampled_profile(new SampledProfile);
   sampled_profile->set_trigger_event(SampledProfile::RESTORE_SESSION);
   sampled_profile->set_ms_after_restore(time_after_restore.InMilliseconds());
   sampled_profile->set_num_tabs_restored(num_tabs_restored);
 
   CollectIfNecessary(std::move(sampled_profile));
   last_session_restore_collection_time_ = base::TimeTicks::Now();
 }
 
 }  // namespace metrics