Version 1.6.60

Cherry-pick: Use toReference instead of asDexReference
CL: https://r8-review.googlesource.com/47616

Bug: 147480426
Change-Id: I51aae47809ea12786302fddc8acee4584f4570c5
diff --git a/src/main/java/com/android/tools/r8/Version.java b/src/main/java/com/android/tools/r8/Version.java
index f4d3d9f..467fc64 100644
--- a/src/main/java/com/android/tools/r8/Version.java
+++ b/src/main/java/com/android/tools/r8/Version.java
@@ -11,7 +11,7 @@
 
   // This field is accessed from release scripts using simple pattern matching.
   // Therefore, changing this field could break our release scripts.
-  public static final String LABEL = "1.6.59";
+  public static final String LABEL = "1.6.60";
 
   private Version() {
   }
diff --git a/src/main/java/com/android/tools/r8/naming/ProguardMapMinifier.java b/src/main/java/com/android/tools/r8/naming/ProguardMapMinifier.java
index c16d718..f68a279 100644
--- a/src/main/java/com/android/tools/r8/naming/ProguardMapMinifier.java
+++ b/src/main/java/com/android/tools/r8/naming/ProguardMapMinifier.java
@@ -486,7 +486,7 @@
       DexString reservedName = getReservedName(definition, name, holder);
       if (reservedName != null) {
         if (!isAvailable.test(reservedName, reference)) {
-          reportReservationError(definition.asDexReference(), reservedName);
+          reportReservationError(definition.toReference(), reservedName);
         }
         return reservedName;
       }