Revert "bump java proto version for new proto/grpc release"

This reverts commit d61cc7b1fb1375946cd1a9f3de4b66f3bfae6275.
diff --git a/gapic/packaging/api_defaults.yaml b/gapic/packaging/api_defaults.yaml
index 9704021..a38b3af 100644
--- a/gapic/packaging/api_defaults.yaml
+++ b/gapic/packaging/api_defaults.yaml
@@ -39,7 +39,7 @@
   ruby:
     lower: '0.6.8'
   java:
-    lower: '0.1.20'
+    lower: '0.1.19'
 
 generated_ga_package_version:
   java:
diff --git a/gapic/packaging/dependencies.yaml b/gapic/packaging/dependencies.yaml
index bc86a47..2c644a0 100644
--- a/gapic/packaging/dependencies.yaml
+++ b/gapic/packaging/dependencies.yaml
@@ -84,7 +84,7 @@
     name_override: googleapis-common-protos
     lower: '1.3.1'
   java:
-    lower: '0.1.20'
+    lower: '0.1.19'
 
 google-iam-v1_version:
   python:
@@ -95,7 +95,7 @@
     name_override: grpc-google-iam-v1
     lower: '0.6.8'
   java:
-    lower: '0.1.20'
+    lower: '0.1.19'
 
 api_common_version:
   java: