Merge branch 'master' into null_safety

* master:
  fvm gitignore
  fvm support.

.fvm/fvm_config.json

@@ -0,0 +1,3 @@
+{
+  "flutterSdkVersion": "1.22.6"
+}

.gitignore

@@ -73,3 +73,4 @@ build/
 !**/ios/**/default.pbxuser
 !**/ios/**/default.perspectivev3
 code_segments.dart
+flutter_sdk

.vscode/settings.json

@@ -1,7 +1,3 @@
 {
-    "cSpell.words": [
-        "ansu",
-        "easyrefresh",
-        "screenutil"
-    ]
+    "dart.flutterSdkPath": "/Users/akufe/apps/flutter"
 }