libroot_build: fix error.ccp build

Since USES_BE_API is set by default on all libroot_build sources, the
error.cpp
was broken, since it wouldn't be exempt from the error mapping. Define
the
BUILDING_HAIKU_ERROR_MAPPER for it directly in the Jamfile, now.

src/build/libroot/Jamfile

@@ -18,17 +18,19 @@ UsePrivateBuildHeaders kernel libroot ;
 	SubDirCcFlags $(defines) ;
 	SubDirC++Flags $(defines) ;
 
-	local defines = [ FDefines
+	defines = [ FDefines
 		HAIKU_BUILD_GENERATED_DIRECTORY="\\\"$(HAIKU_OUTPUT_DIR)\\\""
 	] ;
-	SubDirC++Flags $(defines) ;
 	ObjectC++Flags find_directory.cpp : $(defines) ;
+
+	defines = [ FDefines BUILDING_HAIKU_ERROR_MAPPER=1 ] ;
+	ObjectC++Flags errors.cpp : $(defines) ;
+
+	defines = [ FDefines KMESSAGE_CONTAINER_ONLY=1 ] ;
+	ObjectC++Flags KMessage.cpp : $(defines) ;
+
 }
 
-
-DEFINES += KMESSAGE_CONTAINER_ONLY ;
-ObjectC++Flags KMessage.cpp : $(HOST_BE_API_C++FLAGS) ;
-
 # locate the library
 MakeLocate libroot_build.so : $(HOST_BUILD_COMPATIBILITY_LIB_DIR) ;
 

src/build/libroot/errors.cpp

@@ -1,8 +1,9 @@
+/*
+ * Copyright 2005-2011, Ingo Weinhold, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
 
 
-#define BUILDING_HAIKU_ERROR_MAPPER 1
-#include <BeOSBuildCompatibility.h>
-
 #include <errno.h>
 #include <string.h>