Add installer_util_unittests to the GN windows build

chrome/installer/util/master_preferences_unittest.cc

Index: chrome/installer/util/master_preferences_unittest.cc
diff --git a/chrome/installer/util/master_preferences_unittest.cc b/chrome/installer/util/master_preferences_unittest.cc
index 31f839bd4582a1d5a1172ca34cd04358dc8f9967..74de3aca9141007957739c1902c8435904c07e21 100644
--- a/chrome/installer/util/master_preferences_unittest.cc
+++ b/chrome/installer/util/master_preferences_unittest.cc
@@ -76,7 +76,8 @@ TEST_F(MasterPreferencesTest, ParseDistroParams) {
     "  }\n"
     "} \n";
 
-  EXPECT_TRUE(base::WriteFile(prefs_file(), text, strlen(text)));
+  EXPECT_TRUE(base::WriteFile(prefs_file(), text,
+                              static_cast<int>(strlen(text))));
   installer::MasterPreferences prefs(prefs_file());
   EXPECT_TRUE(prefs.read_from_file());
 
@@ -135,7 +136,8 @@ TEST_F(MasterPreferencesTest, ParseMissingDistroParams) {
     "  }\n"
     "} \n";
 
-  EXPECT_TRUE(base::WriteFile(prefs_file(), text, strlen(text)));
+  EXPECT_TRUE(base::WriteFile(prefs_file(), text,
+                              static_cast<int>(strlen(text))));
   installer::MasterPreferences prefs(prefs_file());
   EXPECT_TRUE(prefs.read_from_file());
 
@@ -194,7 +196,8 @@ TEST_F(MasterPreferencesTest, FirstRunTabs) {
     "  ]\n"
     "} \n";
 
-  EXPECT_TRUE(base::WriteFile(prefs_file(), text, strlen(text)));
+  EXPECT_TRUE(base::WriteFile(prefs_file(), text,
+                              static_cast<int>(strlen(text))));
   installer::MasterPreferences prefs(prefs_file());
   typedef std::vector<std::string> TabsVector;
   TabsVector tabs = prefs.GetFirstRunTabs();
@@ -252,7 +255,8 @@ TEST_F(MasterPreferencesTest, GetInstallPreferencesTest) {
     "     \"verbose_logging\": false\n"
     "  }\n"
     "} \n";
-  EXPECT_TRUE(base::WriteFile(prefs_file, text, strlen(text)));
+  EXPECT_TRUE(base::WriteFile(prefs_file, text,
+                              static_cast<int>(strlen(text))));
 
   // Make sure command line values override the values in master preferences.
   std::wstring cmd_str(