update grpc and dependencies to version 1.20
diff --git a/third_party/BUILD b/third_party/BUILD
index a582add..c927b75 100644
--- a/third_party/BUILD
+++ b/third_party/BUILD
@@ -450,8 +450,8 @@
 java_import(
     name = "opencensus-api",
     jars = [
-        "opencensus/opencensus-api-0.11.0.jar",
-        "opencensus/opencensus-contrib-grpc-metrics-0.11.0.jar",
+        "opencensus/opencensus-api-0.19.2.jar",
+        "opencensus/opencensus-contrib-grpc-metrics-0.19.2.jar",
     ],
 )
 
@@ -513,12 +513,12 @@
 
 java_import(
     name = "netty",
-    jars = ["netty/netty-all-4.1.17.Final.jar"],
+    jars = ["netty/netty-all-4.1.34.Final.jar"],
 )
 
 java_import(
     name = "netty_tcnative",
-    jars = ["netty_tcnative/netty-tcnative-boringssl-static-2.0.7.Final.jar"],
+    jars = ["netty_tcnative/netty-tcnative-boringssl-static-2.0.24.Final.jar"],
 )
 
 java_import(
diff --git a/third_party/grpc/BUILD b/third_party/grpc/BUILD
index 3656b9d..12715fa 100644
--- a/third_party/grpc/BUILD
+++ b/third_party/grpc/BUILD
@@ -42,13 +42,13 @@
 filegroup(
     name = "bootstrap-grpc-jars",
     srcs = [
-        "grpc-auth-1.10.0.jar",
-        "grpc-context-1.10.0.jar",
-        "grpc-core-1.10.0.jar",
-        "grpc-netty-1.10.0.jar",
-        "grpc-protobuf-1.10.0.jar",
-        "grpc-protobuf-lite-1.10.0.jar",
-        "grpc-stub-1.10.0.jar",
+        "grpc-auth-1.20.0.jar",
+        "grpc-context-1.20.0.jar",
+        "grpc-core-1.20.0.jar",
+        "grpc-netty-1.20.0.jar",
+        "grpc-protobuf-1.20.0.jar",
+        "grpc-protobuf-lite-1.20.0.jar",
+        "grpc-stub-1.20.0.jar",
     ],
 )
 
diff --git a/third_party/grpc/README.bazel.md b/third_party/grpc/README.bazel.md
index 3abdc4d..f647c02 100644
--- a/third_party/grpc/README.bazel.md
+++ b/third_party/grpc/README.bazel.md
@@ -19,4 +19,4 @@
 
 # How to update the Java code:
 
-Download the necessary jars at version `1.10.0` from maven central.
+Download the necessary jars at version `1.20.0` from maven central.
diff --git a/third_party/grpc/grpc-auth-1.20.0.jar b/third_party/grpc/grpc-auth-1.20.0.jar
new file mode 100644
index 0000000..ef7ddad
--- /dev/null
+++ b/third_party/grpc/grpc-auth-1.20.0.jar
Binary files differ
diff --git a/third_party/grpc/grpc-context-1.20.0.jar b/third_party/grpc/grpc-context-1.20.0.jar
new file mode 100644
index 0000000..1709dbe
--- /dev/null
+++ b/third_party/grpc/grpc-context-1.20.0.jar
Binary files differ
diff --git a/third_party/grpc/grpc-core-1.20.0.jar b/third_party/grpc/grpc-core-1.20.0.jar
new file mode 100644
index 0000000..a44ec18
--- /dev/null
+++ b/third_party/grpc/grpc-core-1.20.0.jar
Binary files differ
diff --git a/third_party/grpc/grpc-netty-1.20.0.jar b/third_party/grpc/grpc-netty-1.20.0.jar
new file mode 100644
index 0000000..42a96d1
--- /dev/null
+++ b/third_party/grpc/grpc-netty-1.20.0.jar
Binary files differ
diff --git a/third_party/grpc/grpc-protobuf-1.20.0.jar b/third_party/grpc/grpc-protobuf-1.20.0.jar
new file mode 100644
index 0000000..c0103c1
--- /dev/null
+++ b/third_party/grpc/grpc-protobuf-1.20.0.jar
Binary files differ
diff --git a/third_party/grpc/grpc-protobuf-lite-1.20.0.jar b/third_party/grpc/grpc-protobuf-lite-1.20.0.jar
new file mode 100644
index 0000000..f96144f
--- /dev/null
+++ b/third_party/grpc/grpc-protobuf-lite-1.20.0.jar
Binary files differ
diff --git a/third_party/grpc/grpc-stub-1.20.0.jar b/third_party/grpc/grpc-stub-1.20.0.jar
new file mode 100644
index 0000000..958602f
--- /dev/null
+++ b/third_party/grpc/grpc-stub-1.20.0.jar
Binary files differ
diff --git a/third_party/netty/README.bazel.md b/third_party/netty/README.bazel.md
index 7159617..f4bc963 100644
--- a/third_party/netty/README.bazel.md
+++ b/third_party/netty/README.bazel.md
@@ -1,2 +1,2 @@
-To reproduce this tree, download `netty-4.1.17.Final.jar` from Maven Central. It's under the path
+To reproduce this tree, download `netty-4.1.34.Final.jar` from Maven Central. It's under the path
 `io.netty / netty-all` .
diff --git a/third_party/netty/netty-all-4.1.34.Final.jar b/third_party/netty/netty-all-4.1.34.Final.jar
new file mode 100644
index 0000000..cd89f34
--- /dev/null
+++ b/third_party/netty/netty-all-4.1.34.Final.jar
Binary files differ
diff --git a/third_party/netty_tcnative/netty-tcnative-boringssl-static-2.0.24.Final.jar b/third_party/netty_tcnative/netty-tcnative-boringssl-static-2.0.24.Final.jar
new file mode 100644
index 0000000..c3e5149
--- /dev/null
+++ b/third_party/netty_tcnative/netty-tcnative-boringssl-static-2.0.24.Final.jar
Binary files differ
diff --git a/third_party/opencensus/README.md b/third_party/opencensus/README.md
index 7c342c3..8445239 100644
--- a/third_party/opencensus/README.md
+++ b/third_party/opencensus/README.md
@@ -1,2 +1,2 @@
 Download the opencensus-api and opencensus-contrib-grpc-metrics artifact
-from maven central. We currently use version 0.11.0.
+from maven central. We currently use version 0.19.2.
diff --git a/third_party/opencensus/opencensus-api-0.19.2.jar b/third_party/opencensus/opencensus-api-0.19.2.jar
new file mode 100644
index 0000000..c9427f9
--- /dev/null
+++ b/third_party/opencensus/opencensus-api-0.19.2.jar
Binary files differ
diff --git a/third_party/opencensus/opencensus-contrib-grpc-metrics-0.19.2.jar b/third_party/opencensus/opencensus-contrib-grpc-metrics-0.19.2.jar
new file mode 100644
index 0000000..dfb7080
--- /dev/null
+++ b/third_party/opencensus/opencensus-contrib-grpc-metrics-0.19.2.jar
Binary files differ