linux and chromeos: Turn on -Wunused-const-variable.

chrome/browser/policy/url_blacklist_manager.cc

Index: chrome/browser/policy/url_blacklist_manager.cc
diff --git a/chrome/browser/policy/url_blacklist_manager.cc b/chrome/browser/policy/url_blacklist_manager.cc
index 062ed5a2108d93cc6926e203bf522b6de6fb6e08..e4f6db4568cfce18abcda709f14d615468cce35b 100644
--- a/chrome/browser/policy/url_blacklist_manager.cc
+++ b/chrome/browser/policy/url_blacklist_manager.cc
@@ -44,10 +44,10 @@ namespace {
 // Maximum filters per policy. Filters over this index are ignored.
 const size_t kMaxFiltersPerPolicy = 1000;
 
-const char kServiceLoginAuth[] = "/ServiceLoginAuth";
-
 #if !defined(OS_CHROMEOS)
 
+const char kServiceLoginAuth[] = "/ServiceLoginAuth";
+
 bool IsSigninFlowURL(const GURL& url) {
   // Whitelist all the signin flow URLs flagged by the SigninManager.
   if (SigninManager::IsWebBasedSigninFlowURL(url))