Clean up a few more unused globals.

chrome/browser/ui/pdf/pdf_unsupported_feature.cc

Index: chrome/browser/ui/pdf/pdf_unsupported_feature.cc
diff --git a/chrome/browser/ui/pdf/pdf_unsupported_feature.cc b/chrome/browser/ui/pdf/pdf_unsupported_feature.cc
index fde136410bd462f76087f3c2cea98c87cf128e34..520b95167ee37be8cb1f74527f3566f11be2aada 100644
--- a/chrome/browser/ui/pdf/pdf_unsupported_feature.cc
+++ b/chrome/browser/ui/pdf/pdf_unsupported_feature.cc
@@ -54,9 +54,11 @@ using content::WebPluginInfo;
 
 namespace {
 
-static const char kAdobeReaderIdentifier[] = "adobe-reader";
-static const char kAdobeReaderUpdateUrl[] =
-    "http://www.adobe.com/go/getreader_chrome";
+const char kAdobeReaderUpdateUrl[] = "http://www.adobe.com/go/getreader_chrome";
+
+#if defined(OS_WIN) && defined(ENABLE_PLUGIN_INSTALLATION)
+const char kAdobeReaderIdentifier[] = "adobe-reader";
+#endif
 
 // The prompt delegate used to ask the user if they want to use Adobe Reader
 // by default.