Make FileSymlinkException and InconsistentFSException IOExceptions

Most places handle them the same way as IOException, which seems like a safe
default. The places that do care can still throw or catch the more specific type.

PiperOrigin-RevId: 181719688
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/FileFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/FileFunction.java
index 853ab88..74980d2 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/FileFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/FileFunction.java
@@ -252,7 +252,8 @@
         // reported exactly once.
         return null;
       }
-      throw new FileFunctionException(Preconditions.checkNotNull(fse, rootedPath));
+      throw new FileFunctionException(
+          Preconditions.checkNotNull(fse, rootedPath), Transience.PERSISTENT);
     }
 
     return resolveFromAncestors(symlinkTargetRootedPath, env);
@@ -278,15 +279,6 @@
    * {@link FileFunction#compute}.
    */
   private static final class FileFunctionException extends SkyFunctionException {
-
-    public FileFunctionException(InconsistentFilesystemException e, Transience transience) {
-      super(e, transience);
-    }
-
-    public FileFunctionException(FileSymlinkException e) {
-      super(e, Transience.PERSISTENT);
-    }
-
     public FileFunctionException(IOException e, Transience transience) {
       super(e, transience);
     }