Consistently use namespaced base::Version in chrome/installer.

chrome/installer/util/google_update_settings.cc

Index: chrome/installer/util/google_update_settings.cc
diff --git a/chrome/installer/util/google_update_settings.cc b/chrome/installer/util/google_update_settings.cc
index 519c433244e33185eeedf001a562455e80956cd5..747da1c7b64481bbc727f003ced287996ccd71fc 100644
--- a/chrome/installer/util/google_update_settings.cc
+++ b/chrome/installer/util/google_update_settings.cc
@@ -869,7 +869,8 @@ base::string16 GoogleUpdateSettings::GetUninstallCommandLine(
   return cmd_line;
 }
 
-Version GoogleUpdateSettings::GetGoogleUpdateVersion(bool system_install) {
+base::Version GoogleUpdateSettings::GetGoogleUpdateVersion(
+    bool system_install) {
   const HKEY root_key = system_install ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
   base::string16 version;
   RegKey key;
@@ -879,10 +880,10 @@ Version GoogleUpdateSettings::GetGoogleUpdateVersion(bool system_install) {
                KEY_QUERY_VALUE | KEY_WOW64_32KEY) == ERROR_SUCCESS &&
       key.ReadValue(google_update::kRegGoogleUpdateVersion, &version) ==
           ERROR_SUCCESS) {
-    return Version(base::UTF16ToUTF8(version));
+    return base::Version(base::UTF16ToUTF8(version));
   }
 
-  return Version();
+  return base::Version();
 }
 
 base::Time GoogleUpdateSettings::GetGoogleUpdateLastStartedAU(