Generate param traits size methods for IPC files in chrome/ (and traits it depends on).

components/cdm/common/cdm_message_generator.cc

Index: components/cdm/common/cdm_message_generator.cc
diff --git a/components/cdm/common/cdm_message_generator.cc b/components/cdm/common/cdm_message_generator.cc
index 2aabce727a5b72c028f5f1246a63679088ca4b19..3c3e2602371f880cd2098bf31373f3b68a82001c 100644
--- a/components/cdm/common/cdm_message_generator.cc
+++ b/components/cdm/common/cdm_message_generator.cc
@@ -14,6 +14,12 @@
 #include "ipc/struct_destructor_macros.h"
 #include "components/cdm/common/cdm_message_generator.h"
 
+// Generate param traits size methods.
+#include "ipc/param_traits_size_macros.h"
+namespace IPC {
+#include "components/cdm/common/cdm_message_generator.h"
+}
+
 // Generate param traits write methods.
 #include "ipc/param_traits_write_macros.h"
 namespace IPC {