Fix NPE when PATH environment variable is empty

Change-Id: Ic27d509cd5e2d6c855e7d355fc308399d9dc01c9
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit/src/org/eclipse/jgit/util/FS.java

@@ -244,7 +244,20 @@ public abstract class FS {
 		return new File(home).getAbsoluteFile();
 	}
 
+	/**
+	 * Searches the given path to see if it contains one of the given files.
+	 * Returns the first it finds. Returns null if not found or if path is null.
+	 *
+	 * @param path
+	 *            List of paths to search separated by File.pathSeparator
+	 * @param lookFor
+	 *            Files to search for in the given path
+	 * @return the first match found, or null
+	 **/
 	static File searchPath(final String path, final String... lookFor) {
+		if (path == null)
+			return null;
+
 		for (final String p : path.split(File.pathSeparator)) {
 			for (String command : lookFor) {
 				final File e = new File(p, command);