Make DepsTrackingReporter handle Windows path separators (#1503)

* Handle Windows path seps in DepsTrackingReporter

* Removed unused import in DepsTrackingReporter.java

Author: crt-31

src/java/io/bazel/rulesscala/scalac/reporter/DepsTrackingReporter.java

@@ -91,6 +91,9 @@ public void info0(Position pos, String msg, Severity severity, boolean force) {
   private void parseOpenedJar(String msg) {
     String jar = msg.split(":")[1];
 
+    //normalize path separators (scalac passes os-specific path separators.)
+    jar = jar.replace("\\", "/");
+
     // track only jars from dependency targets
     // this should exclude things like rt.jar which come from JDK
     if (jarToTarget.containsKey(jar) || indirectJarToTarget.containsKey(jar)) {