Generate the print messages in components/printing

components/printing/common/print_messages.h

Index: components/printing/common/print_messages.h
diff --git a/components/printing/common/print_messages.h b/components/printing/common/print_messages.h
index effc2f244abc3aeab9d86fe8b6079b3adfa335a3..de4e00555f6556ceb0af5dd2cf3a43e997604663 100644
--- a/components/printing/common/print_messages.h
+++ b/components/printing/common/print_messages.h
@@ -14,11 +14,15 @@
 #include "printing/page_range.h"
 #include "printing/page_size_margins.h"
 #include "printing/print_job_constants.h"
+#include "printing/printing_param_traits_macros.h"
 #include "third_party/WebKit/public/web/WebPrintScalingOption.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/ipc/gfx_param_traits.h"
 #include "ui/gfx/native_widget_types.h"
 
+// Force multiple inclusion of the param traits file to generate all methods.
+#undef PRINTING_PRINTING_PARAM_TRAITS_MACROS_H_

[dgn, 2015/01/19 18:09:31]

Inspired by: 
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/common/impo...

+
 #ifndef COMPONENTS_PRINTING_COMMON_PRINT_MESSAGES_H_
 #define COMPONENTS_PRINTING_COMMON_PRINT_MESSAGES_H_
 
@@ -86,13 +90,8 @@ struct PrintHostMsg_SetOptionsFromDocument_Params {
 
 #define IPC_MESSAGE_START PrintMsgStart
 
-IPC_ENUM_TRAITS_MAX_VALUE(printing::MarginType,

[Vitaly Buka (NO REVIEWS), 2015/01/21 00:59:59]

do you need to them to separate file?
can we just have one traits here and one in utilities?

[dgn, 2015/01/21 18:24:24]

Then since they are processed by different generators, the functions are defined
twice. 

-                          printing::MARGIN_TYPE_LAST)
 IPC_ENUM_TRAITS_MAX_VALUE(blink::WebPrintScalingOption,
                           blink::WebPrintScalingOptionLast)
-IPC_ENUM_TRAITS_MIN_MAX_VALUE(printing::DuplexMode,
-                              printing::UNKNOWN_DUPLEX_MODE,
-                              printing::SHORT_EDGE)
 
 // Parameters for a render request.
 IPC_STRUCT_TRAITS_BEGIN(PrintMsg_Print_Params)