Remove "base/values.h" import from "base/location.h", fix up downstream files.

content/browser/renderer_host/pepper_message_filter.h

Index: content/browser/renderer_host/pepper_message_filter.h
diff --git a/content/browser/renderer_host/pepper_message_filter.h b/content/browser/renderer_host/pepper_message_filter.h
index c2b9a51103cff5d0fc239e2e0d108626c7751aa3..43b47cb47144c0b962be7fb89a4cdd3f829b7793 100644
--- a/content/browser/renderer_host/pepper_message_filter.h
+++ b/content/browser/renderer_host/pepper_message_filter.h
@@ -20,13 +20,16 @@
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/c/pp_stdint.h"
 
-class ListValue;
 class PepperTCPServerSocket;
 class PepperTCPSocket;
 class PepperUDPSocket;
 struct PP_HostResolver_Private_Hint;
 struct PP_NetAddress_Private;
 
+namespace base {
+class ListValue;
+}
+
 namespace content {
 class ResourceContext;
 }