Add a new protobuf message named Upload to upload build metrics.

A new protobuf message named Upload is defined to send build metrics
to the Android Build Server API after a build is completed. These
metrics are collected from googlers only, as described in
go/local-developers-metrics-wfh.

Bug: b/140638454
Test: m nothing
Change-Id: I5e49b5ace053913be2b75673cb1375f4cef37825
diff --git a/ui/metrics/Android.bp b/ui/metrics/Android.bp
index 529639d..3596e10 100644
--- a/ui/metrics/Android.bp
+++ b/ui/metrics/Android.bp
@@ -17,6 +17,7 @@
     pkgPath: "android/soong/ui/metrics",
     deps: [
         "golang-protobuf-proto",
+        "soong-ui-metrics_upload_proto",
         "soong-ui-metrics_proto",
         "soong-ui-tracer",
     ],
@@ -35,3 +36,11 @@
     ],
 }
 
+bootstrap_go_package {
+    name: "soong-ui-metrics_upload_proto",
+    pkgPath: "android/soong/ui/metrics/upload_proto",
+    deps: ["golang-protobuf-proto"],
+    srcs: [
+        "upload_proto/upload.pb.go",
+    ],
+}