Direct host output to a specific log file.

remoting/host/constants_mac.h

Index: remoting/host/constants_mac.h
===================================================================
--- remoting/host/constants_mac.h	(revision 181302)
+++ remoting/host/constants_mac.h	(working copy)
@@ -46,6 +46,12 @@
 // The .plist file for the Chromoting service.
 extern const char kServicePlistPath[];
 
+// Path to the host log file
+extern const char kLogFilePath[];
+
+// Path to the log config file
+extern const char kLogFileConfigPath[];
+
 // The branded and unbranded names for the uninstaller.
 // This is the only file that changes names based on branding. We define both
 // because we want local dev builds to be able to clean up both files.