Fix a bug whereupon a String was compared to a PathFragment.

--
PiperOrigin-RevId: 150623623
MOS_MIGRATED_REVID=150623623
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/Runfiles.java b/src/main/java/com/google/devtools/build/lib/analysis/Runfiles.java
index a087ee4..b311ebb 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/Runfiles.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/Runfiles.java
@@ -556,7 +556,8 @@
     }
 
     private PathFragment checkForWorkspace(PathFragment path) {
-      sawWorkspaceName = sawWorkspaceName || path.getSegment(0).equals(workspaceName);
+      sawWorkspaceName = sawWorkspaceName
+          || path.getSegment(0).equals(workspaceName.getPathString());
       return path;
     }