Version 8.4.20-dev

Change-Id: I875e2b9ccd85c1e54e46369cecef3dab59ea7743
diff --git a/src/main/java/com/android/tools/r8/Version.java b/src/main/java/com/android/tools/r8/Version.java
index 878e412..40284f0 100644
--- a/src/main/java/com/android/tools/r8/Version.java
+++ b/src/main/java/com/android/tools/r8/Version.java
@@ -13,7 +13,7 @@
 
   // 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 = "8.4.19-dev";
+  public static final String LABEL = "8.4.20-dev";
 
   private Version() {
   }