refactor: change to default proto.js export (#96)

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https://source.cloud.google.com/results/invocations/1630485f-7526-4afd-9c13-b5660664d6a2/targets

protos/protos.js

@@ -28,7 +28,7 @@
     var $Reader = $protobuf.Reader, $Writer = $protobuf.Writer, $util = $protobuf.util;
 
     // Exported root namespace
-    var $root = $protobuf.roots["default"] || ($protobuf.roots["default"] = {});
+    var $root = $protobuf.roots._google_cloud_cloudbuild_1_5_0_protos || ($protobuf.roots._google_cloud_cloudbuild_1_5_0_protos = {});
 
     $root.google = (function() {
 

synth.metadata

@@ -1,5 +1,22 @@
 {
-  "updateTime": "2020-03-31T19:22:01.525662Z",
+  "updateTime": "2020-04-03T11:25:24.226680Z",
+  "sources": [
+    {
+      "git": {
+        "name": "googleapis",
+        "remote": "https://github.com/googleapis/googleapis.git",
+        "sha": "3d5d228a58bdf875e6147b228db3159010c735ee",
+        "internalRef": "304500143"
+      }
+    },
+    {
+      "git": {
+        "name": "synthtool",
+        "remote": "https://github.com/googleapis/synthtool.git",
+        "sha": "99820243d348191bc9c634f2b48ddf65096285ed"
+      }
+    }
+  ],
   "destinations": [
     {
       "client": {