Set jdk 11 as the default R8 system runtime.

Bug: b/227300698
Change-Id: If3ba63f579e8c23bbdd854dd66223ef5e2a7c7b5
diff --git a/tools/jdk.py b/tools/jdk.py
index ea6be86..c9cb628 100755
--- a/tools/jdk.py
+++ b/tools/jdk.py
@@ -11,7 +11,7 @@
 JDK_DIR = os.path.join(defines.THIRD_PARTY, 'openjdk')
 
 def GetJdkHome():
-  return GetJdk9Home()
+  return GetJdk11Home()
 
 def GetJdk11Home():
   root = os.path.join(JDK_DIR, 'jdk-11')