Fix find-jdk-tools-jar to be cygwin-friendly.

Change-Id: I9cf2035026725fd1ba8a014b484262ed1acc1df4

core/find-jdk-tools-jar.sh

@@ -6,9 +6,9 @@ else
 	echo "Please-install-JDK-6,-which-you-can-download-from-java.sun.com"
 	exit 1
     fi
-    while [ -L $JAVAC ] ; do
-        LSLINE=$(ls -l $JAVAC)
-        JAVAC=$(echo -n $LSLINE | sed -e "s/.* -> //")
+    while [ -L "$JAVAC" ] ; do
+        LSLINE=$(ls -l "$JAVAC")
+        JAVAC=$(echo -n "$LSLINE" | sed -e "s/.* -> //")
     done
     echo $JAVAC | sed -e "s:\(.*\)/bin/javac.*:\\1/lib/tools.jar:"
 fi