Remove unnecessary lines am: a3bff77ab8

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/exoplayer/+/11833774

Change-Id: I993145493225bb5aa923a0b7a1a72e7979e042f5
diff --git a/update.py b/update.py
index e435ced..3579764 100755
--- a/update.py
+++ b/update.py
@@ -10,8 +10,6 @@
 import re
 import datetime
 
-BRANCH_UPSTREAM_DEV = "goog/upstream-dev-v2"
-BRANCH_USPTREAM_RELEASE = "goog/upstream-release-v2"
 TEMPORARY_TREE_CHECKOUT_DIR = ".temp_tree/"
 TREE_LOCATION = "tree/"
 METADATA_FILE = "METADATA"