Update SplitString calls in components

components/variations/study_filtering_unittest.cc

Index: components/variations/study_filtering_unittest.cc
diff --git a/components/variations/study_filtering_unittest.cc b/components/variations/study_filtering_unittest.cc
index d8f7f91114c8fa03c6eb12f453cb1cacaa4c6c8d..66b30efd1b24521c06176567fa332e9db7bfafe9 100644
--- a/components/variations/study_filtering_unittest.cc
+++ b/components/variations/study_filtering_unittest.cc
@@ -139,11 +139,11 @@ TEST(VariationsStudyFilteringTest, CheckStudyLocale) {
   };
 
   for (size_t i = 0; i < arraysize(test_cases); ++i) {
-    std::vector<std::string> filter_locales;
     Study_Filter filter;
-    base::SplitString(test_cases[i].filter_locales, ',', &filter_locales);
-    for (size_t j = 0; j < filter_locales.size(); ++j)
-      filter.add_locale(filter_locales[j]);
+    for (const std::string& locale : base::SplitString(
+             test_cases[i].filter_locales, ",",
+             base::KEEP_WHITESPACE, base::SPLIT_WANT_ALL))
+      filter.add_locale(locale);
     EXPECT_EQ(test_cases[i].en_us_result,
               internal::CheckStudyLocale(filter, "en-US"));
     EXPECT_EQ(test_cases[i].en_ca_result,
@@ -355,16 +355,15 @@ TEST(VariationsStudyFilteringTest, CheckStudyHardwareClass) {
 
   for (size_t i = 0; i < arraysize(test_cases); ++i) {
     Study_Filter filter;
-    std::vector<std::string> hardware_class;
-    base::SplitString(test_cases[i].hardware_class, ',', &hardware_class);
-    for (size_t j = 0; j < hardware_class.size(); ++j)
-      filter.add_hardware_class(hardware_class[j]);
+    for (const std::string& cur : base::SplitString(
+             test_cases[i].hardware_class, ",",
+             base::KEEP_WHITESPACE, base::SPLIT_WANT_ALL))
+      filter.add_hardware_class(cur);
 
-    std::vector<std::string> exclude_hardware_class;
-    base::SplitString(test_cases[i].exclude_hardware_class, ',',
-                      &exclude_hardware_class);
-    for (size_t j = 0; j < exclude_hardware_class.size(); ++j)
-      filter.add_exclude_hardware_class(exclude_hardware_class[j]);
+    for (const std::string& cur : base::SplitString(
+             test_cases[i].exclude_hardware_class, ",",
+             base::KEEP_WHITESPACE, base::SPLIT_WANT_ALL))
+      filter.add_exclude_hardware_class(cur);
 
     EXPECT_EQ(test_cases[i].expected_result,
               internal::CheckStudyHardwareClass(
@@ -406,14 +405,13 @@ TEST(VariationsStudyFilteringTest, CheckStudyCountry) {
 
   for (const auto& test : test_cases) {
     Study_Filter filter;
-    std::vector<std::string> countries;
-    base::SplitString(test.country, ',', &countries);
-    for (const std::string& country : countries)
+    for (const std::string& country : base::SplitString(
+             test.country, ",", base::KEEP_WHITESPACE, base::SPLIT_WANT_ALL))
       filter.add_country(country);
 
-    std::vector<std::string> exclude_countries;
-    base::SplitString(test.exclude_country, ',', &exclude_countries);
-    for (const std::string& exclude_country : exclude_countries)
+    for (const std::string& exclude_country : base::SplitString(
+             test.exclude_country, ",",
+             base::KEEP_WHITESPACE, base::SPLIT_WANT_ALL))
       filter.add_exclude_country(exclude_country);
 
     EXPECT_EQ(test.expected_result,