Generate param traits even when shared by mutliple message files.

content/public/common/common_param_traits.h

Index: content/public/common/common_param_traits.h
===================================================================
--- content/public/common/common_param_traits.h	(revision 143049)
+++ content/public/common/common_param_traits.h	(working copy)
@@ -17,7 +17,6 @@
 
 #include "base/memory/ref_counted.h"
 #include "content/common/content_export.h"
-#include "content/public/common/console_message_level.h"
 #include "content/public/common/page_transition_types.h"
 #include "content/public/common/security_style.h"
 #include "googleurl/src/gurl.h"
@@ -29,6 +28,11 @@
 #include "ui/surface/transport_dib.h"
 #include "webkit/glue/resource_type.h"
 
+// Explicitly guarded include of _defs.h files in header files.

[jam, 2012/06/20 21:55:48]

even though I see why, it's odd reading that ifdef in  traits/message files.

how many traits does this cover? i guess you'd want to get rid of
common_param_traits in content/chrome completely?

+#ifndef CONTENT_PUBLIC_COMMON_COMMON_PARAM_TRAITS_DEFS_H_
+#include "content/public/common/common_param_traits_defs.h"
+#endif
+
 class SkBitmap;
 
 namespace content {
@@ -248,14 +252,6 @@
   typedef int Type;
 };
 
-template<>
-struct CONTENT_EXPORT ParamTraits<content::ConsoleMessageLevel> {
-  typedef content::ConsoleMessageLevel param_type;
-  static void Write(Message* m, const param_type& p);
-  static bool Read(const Message* m, PickleIterator* iter, param_type* r);
-  static void Log(const param_type& p, std::string* l);
-};
-
 }  // namespace IPC
 
 #endif  // CONTENT_PUBLIC_COMMON_COMMON_PARAM_TRAITS_H_