Improve the accuracy of local provider error reporting

[Sergio Villar Senin <svillar igalia com>]

Hi,

this patch sets the error CAMEL_EXCEPTION_FOLDER_CREATE instead of
CAMEL_EXCEPTION_STORE_NO_FOLDER when the get_folder method is called
with CAMEL_STORE_FOLDER_CREATE flag by create_folder.

This way we'll get a TNY_SERVICE_ERROR_FOLDER_CREATE instead of a
TNY_SERVICE_ERROR_FOLDER_IS_UNKNOWN

Br

Index: libtinymail-camel/camel-lite/camel/providers/local/camel-local-store.c
===================================================================
--- libtinymail-camel/camel-lite/camel/providers/local/camel-local-store.c	(revision 3628)
+++ libtinymail-camel/camel-lite/camel/providers/local/camel-local-store.c	(working copy)
@@ -201,8 +201,8 @@
 
 	/* need to create the dir heirarchy */
 	if (g_mkdir_with_parents (path, 0777) == -1 && errno != EEXIST) {
-		camel_exception_setv (ex, CAMEL_EXCEPTION_STORE_NO_FOLDER,
-				      _("Cannot get folder: %s: %s"),
+		camel_exception_setv (ex, CAMEL_EXCEPTION_FOLDER_CREATE,
+				      _("Cannot create folder: %s: %s"),
 				      path, g_strerror (errno));
 		return NULL;
 	}