Upgrade guava to 26.0-jre

Change-Id: I21ee2fd2d9dd2e4335b56aeea5f25c674a5605fa
diff --git a/WORKSPACE b/WORKSPACE
index adcfae2..b7e6659 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -34,8 +34,8 @@
 
 maven_jar(
     name = "guava",
-    artifact = "com.google.guava:guava:25.1-jre",
-    sha1 = "6c57e4b22b44e89e548b5c9f70f0c45fe10fb0b4",
+    artifact = "com.google.guava:guava:26.0-jre",
+    sha1 = "6a806eff209f36f635f943e16d97491f00f6bfab",
 )
 
 maven_jar(