flutter pub upgrade (#524)

jsonexample/pubspec.lock

@@ -7,14 +7,14 @@ packages:
       name: _fe_analyzer_shared
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "3.0.0"
+    version: "7.0.0"
   analyzer:
     dependency: transitive
     description:
       name: analyzer
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.39.8"
+    version: "0.39.17"
   args:
     dependency: transitive
     description:
@@ -42,7 +42,7 @@ packages:
       name: build
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.2"
+    version: "1.3.0"
   build_config:
     dependency: transitive
     description:
@@ -63,21 +63,21 @@ packages:
       name: build_resolvers
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.7"
+    version: "1.3.11"
   build_runner:
     dependency: "direct dev"
     description:
       name: build_runner
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.9.0"
+    version: "1.10.0"
   build_runner_core:
     dependency: transitive
     description:
       name: build_runner_core
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "5.1.0"
+    version: "5.2.0"
   built_collection:
     dependency: "direct main"
     description:
@@ -120,6 +120,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.2"
+  cli_util:
+    dependency: transitive
+    description:
+      name: cli_util
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.2.0"
   clock:
     dependency: transitive
     description:
@@ -133,7 +140,7 @@ packages:
       name: code_builder
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "3.2.1"
+    version: "3.4.0"
   collection:
     dependency: transitive
     description:
@@ -154,14 +161,14 @@ packages:
       name: crypto
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.4"
+    version: "2.1.5"
   csslib:
     dependency: transitive
     description:
       name: csslib
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.16.1"
+    version: "0.16.2"
   dart_style:
     dependency: transitive
     description:
@@ -241,7 +248,7 @@ packages:
       name: js
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.6.1+1"
+    version: "0.6.2"
   json_annotation:
     dependency: "direct main"
     description:
@@ -255,7 +262,7 @@ packages:
       name: json_serializable
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "3.3.0"
+    version: "3.4.0"
   logging:
     dependency: transitive
     description:
@@ -283,21 +290,21 @@ packages:
       name: mime
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.9.6+3"
+    version: "0.9.7"
   node_interop:
     dependency: transitive
     description:
       name: node_interop
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.0.3"
+    version: "1.1.1"
   node_io:
     dependency: transitive
     description:
       name: node_io
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0"
+    version: "1.1.1"
   package_config:
     dependency: transitive
     description:
@@ -353,7 +360,7 @@ packages:
       name: shelf
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.7.5"
+    version: "0.7.8"
   shelf_web_socket:
     dependency: transitive
     description:
@@ -372,7 +379,7 @@ packages:
       name: source_gen
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.9.5"
+    version: "0.9.6"
   source_span:
     dependency: transitive
     description: