Replace fprintf with mojo logging macro.

mojo/public/cpp/bindings/lib/validation_errors.cc

Index: mojo/public/cpp/bindings/lib/validation_errors.cc
diff --git a/mojo/public/cpp/bindings/lib/validation_errors.cc b/mojo/public/cpp/bindings/lib/validation_errors.cc
index ed5904d396318d123add33def50deda889688078..2b4392cd3881d51a1a9274de68c8e570cb68f8a8 100644
--- a/mojo/public/cpp/bindings/lib/validation_errors.cc
+++ b/mojo/public/cpp/bindings/lib/validation_errors.cc
@@ -5,7 +5,8 @@
 #include "mojo/public/cpp/bindings/lib/validation_errors.h"
 
 #include <assert.h>
-#include <stdio.h>
+
+#include "mojo/public/cpp/environment/logging.h"
 
 namespace mojo {
 namespace internal {
@@ -44,8 +45,7 @@ void ReportValidationError(ValidationError error) {
   if (g_validation_error_observer) {

[viettrungluu, 2014/06/20 01:11:18]

FWIW, you can get rid of the braces if you feel like.

[yzshen1, 2014/06/20 05:41:24]

Done.

     g_validation_error_observer->set_last_error(error);
   } else {
-    // TODO(yzshen): Consider adding better logging support.
-    fprintf(stderr, "Invalid message: %s\n", ValidationErrorToString(error));
+    MOJO_LOG(ERROR) << "Invalid message: " << ValidationErrorToString(error);
   }
 }