Support symlinking to dart-sdk executables on Linux and Mac.

sdk/bin/dartanalyzer

 #!/bin/bash --posix
 # Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 set -e
 
 # Setting SCRIPT_DIR this way is ugly, but is needed to handle the case where
-# dart-sdk/bin has been symlinked to. On MacOS, readlink doesn't work
-# with this case.
-SCRIPT_DIR="$(cd "${0%/*}" ; pwd -P)"
+# dart-sdk/bin has been symlinked to. On MacOS, readlink -f doesn't work with
+# this case.
+SCRIPT=`readlink "$0" || echo "$0"`
+SCRIPT_DIR="$(cd "${SCRIPT%/*}" ; pwd -P)"
 DART_ANALYZER_HOME="$(cd "${SCRIPT_DIR%/*}" ; pwd -P)"
 
 FOUND_BATCH=0
 FOUND_SDK=0
 for ARG in "$@"
 do
   case $ARG in
     -batch|--batch)
       FOUND_BATCH=1
       ;;
@@ skipping 48 matching lines @@
   # On other architectures
   # -batch invocations will do better with a server vm
   # invocations for analyzing a single file do better with a client vm
   if [ $FOUND_BATCH -eq 0 ] ; then
     EXTRA_JVMARGS+=" -client "
   fi
 fi
 
 exec java $EXTRA_JVMARGS $DART_JVMARGS -ea -jar \
   "$DART_ANALYZER_LIBS/dartanalyzer.jar" "${DART_SDK[@]}" $@