metrics cleanup and fixes.

src/platform/init/dump-boot-stats.conf

 # Copyright (c) 2009 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # dump-boot-stats
 #
 # when login-prompt-ready is received, grabs the current uptime and
 # disk stats.  Also sends uptime to metrics client for perf dashboard
 
 start on login-prompt-ready
 
 # This is run-once rather than a service.
 task
 
 script
   UPTIME_STATS=`cat /proc/uptime`
   DISK_STATS=`cat /sys/block/sda/stat`
   
   BOOT_TIME=`echo $UPTIME_STATS | cut -f 1 -d ' '`
-  BOOT_TIME_INT=`echo $BOOT_TIME | cut -f 1 -d '.'`
-  BOOT_TIME_FRACT=`echo $BOOT_TIME | cut -f 2 -d '.'`
-  BOOT_TIME_MSECS=$((BOOT_TIME_INT * 1000 + BOOT_TIME_FRACT * 10))
-
   SECTORS_READ=`echo $DISK_STATS | cut -f 3 -d ' '`
   SECTORS_WRITTEN=`echo $DISK_STATS | cut -f 7 -d ' '`
 
-  /usr/bin/metrics_client BootTime $BOOT_TIME_MSECS &
+  /usr/bin/metrics_client -t BootTime $BOOT_TIME &
   /usr/bin/metrics_client BootSectorsRead $SECTORS_READ &
   /usr/bin/metrics_client BootSectorsWritten $SECTORS_WRITTEN &    
   
   echo $UPTIME_STATS > /tmp/uptime-login-prompt-ready
   echo $DISK_STATS > /tmp/disk-login-prompt-ready
 end script