Fix FilteredClassPathTest on Windows to not assume the use of Path objects.

All entries in zip files use '/' and not file separator. At this point
we only have support for filtered class paths from archives and therefore
we never need to map between '/' and '\'.

R=sgjesse@google.com

Change-Id: Ic71dcd309efd78f78242e57c8b48584dcea21b60
diff --git a/src/main/java/com/android/tools/r8/shaking/FilteredClassPath.java b/src/main/java/com/android/tools/r8/shaking/FilteredClassPath.java
index b432371..c67af00 100644
--- a/src/main/java/com/android/tools/r8/shaking/FilteredClassPath.java
+++ b/src/main/java/com/android/tools/r8/shaking/FilteredClassPath.java
@@ -46,10 +46,6 @@
     return path;
   }
 
-  public boolean matchesFile(Path path) {
-    return matchesFile(path.toString());
-  }
-
   public boolean matchesFile(String name) {
     if (isUnfiltered()) {
       return true;
@@ -67,7 +63,7 @@
   }
 
   private boolean containsFileSeparator(String string) {
-    return string.indexOf(File.separatorChar) != -1;
+    return string.indexOf('/') != -1;
   }
 
   private boolean matchAgainstFileName(String fileName, int namePos, String pattern,
@@ -99,7 +95,7 @@
         }
       } else {
         for (int i = namePos; i < fileName.length(); i++) {
-          if (!includeFileSeparators && fileName.charAt(i) == File.separatorChar) {
+          if (!includeFileSeparators && fileName.charAt(i) == '/') {
             return false;
           }
           if (matchAgainstFileName(fileName, i, pattern, patternPos + 1)) {
diff --git a/src/test/java/com/android/tools/r8/shaking/FilteredClassPathTest.java b/src/test/java/com/android/tools/r8/shaking/FilteredClassPathTest.java
index f27813e..7c243ae 100644
--- a/src/test/java/com/android/tools/r8/shaking/FilteredClassPathTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/FilteredClassPathTest.java
@@ -34,16 +34,8 @@
 
   private void testPath(List<String> filters, List<String> positives, List<String> negatives) {
     FilteredClassPath path = makeFilteredClassPath(filters);
-    Assert.assertTrue(
-        positives.stream().map(FilteredClassPathTest::adaptFileSeparator).map(Paths::get)
-            .allMatch(path::matchesFile));
-    Assert.assertFalse(
-        negatives.stream().map(FilteredClassPathTest::adaptFileSeparator).map(Paths::get)
-            .allMatch(path::matchesFile));
-  }
-
-  private static String adaptFileSeparator(String s) {
-    return s.replace('/', File.separatorChar);
+    Assert.assertTrue(positives.stream().allMatch(path::matchesFile));
+    Assert.assertFalse(negatives.stream().allMatch(path::matchesFile));
   }
 
   private static FilteredClassPath makeFilteredClassPath(List<String> filters) {
@@ -51,9 +43,7 @@
   }
 
   private static FilteredClassPath makeFilteredClassPath(Path path, List<String> filters) {
-    return new FilteredClassPath(path,
-        filters.stream().map(FilteredClassPathTest::adaptFileSeparator)
-            .collect(ImmutableList.toImmutableList()));
+    return new FilteredClassPath(path, ImmutableList.copyOf(filters));
   }
 
   @Test