Fix build server tests on Windows

Change-Id: I85ed935936facb8d337b5abc471c5227e3de21d9

appinventor/buildserver/tests/com/google/appinventor/buildserver/YailAndroidTest.java

@@ -22,13 +22,15 @@ import static org.junit.Assert.assertEquals;
 public class YailAndroidTest {
   private Scheme scheme;
 
-  private static final String YAIL_SCHEME_TESTS = TestUtils.APP_INVENTOR_ROOT_DIR +
+  private static final String YAIL_SCHEME_TESTS =
+      TestUtils.windowsToUnix(TestUtils.APP_INVENTOR_ROOT_DIR) +
       "/buildserver/tests/com/google/appinventor/buildserver/YailEvalTest.scm";
 
   @Before
   public void setUp() throws Exception {
     scheme = new Scheme();
     String yailRuntimeLibrary = Compiler.getResource(Compiler.YAIL_RUNTIME);
+    yailRuntimeLibrary = TestUtils.windowsToUnix(yailRuntimeLibrary);
     try {
       scheme.eval("(load \"" + yailRuntimeLibrary + "\")");
       scheme.eval("(load \"" + YAIL_SCHEME_TESTS + "\")");

appinventor/buildserver/tests/com/google/appinventor/buildserver/YailEvalTest.java

@@ -32,13 +32,15 @@ import java.util.Map;
 public class YailEvalTest extends TestCase {
   private Scheme scheme;
 
-  private static final String YAIL_SCHEME_TESTS = TestUtils.APP_INVENTOR_ROOT_DIR +
+  private static final String YAIL_SCHEME_TESTS =
+      TestUtils.windowsToUnix(TestUtils.APP_INVENTOR_ROOT_DIR) +
       "/buildserver/tests/com/google/appinventor/buildserver/YailEvalTest.scm";
 
   @Override
   public void setUp() throws Exception {
     scheme = new Scheme();
     String yailRuntimeLibrary = Compiler.getResource(Compiler.YAIL_RUNTIME);
+    yailRuntimeLibrary = TestUtils.windowsToUnix(yailRuntimeLibrary);
     try {
       scheme.eval("(load \"" + yailRuntimeLibrary + "\")");
       scheme.eval("(load \"" + YAIL_SCHEME_TESTS + "\")");

appinventor/common/src/com/google/appinventor/common/testutils/TestUtils.java

@@ -31,8 +31,11 @@ public class TestUtils {
       dir = dir.getParentFile();
     }
 
-    assert false;
-    return null;  //  to make compiler happy
+    throw new RuntimeException("Unable to locate App Inventor root");
+  }
+
+  public static String windowsToUnix(String path) {
+    return path.replaceAll("\\\\", "/");
   }
 
 }