Update patch version for release - new version is 1.6.10-dev

Change-Id: If176faaa162cb52f778c7026d03ed8d1c54bc737
diff --git a/src/main/java/com/android/tools/r8/Version.java b/src/main/java/com/android/tools/r8/Version.java
index fc8c529..d8f1e05 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 = "1.6.9-dev";
+  public static final String LABEL = "1.6.10-dev";
 
   private Version() {
   }