[Retrace] Add getRenamedSignature because it is used in google3

Bug: b/248217095
Change-Id: Ia05020e76a382f11230bd4b5d917993c2b3006d9
diff --git a/src/main/java/com/android/tools/r8/naming/MemberNaming.java b/src/main/java/com/android/tools/r8/naming/MemberNaming.java
index 9f3e5ed..043bb4c 100644
--- a/src/main/java/com/android/tools/r8/naming/MemberNaming.java
+++ b/src/main/java/com/android/tools/r8/naming/MemberNaming.java
@@ -87,6 +87,15 @@
     this.position = position;
   }
 
+  /** This is used internally in google3. */
+  @Deprecated
+  public Signature getRenamedSignature() {
+    if (residualSignature != null) {
+      return residualSignature;
+    }
+    return getOriginalSignature().asRenamed(renamedName);
+  }
+
   @Override
   public Signature getOriginalSignature() {
     return signature;