Support conditional type and infer type in Flow (#14573)

Co-authored-by: fisker <lionkay@gmail.com>

tests/unit/__snapshots__/visitor-keys.js.snap

@@ -143,6 +143,12 @@ exports[`visitor keys estree 1`] = `
     "consequent",
     "alternate",
   ],
+  "ConditionalTypeAnnotation": [
+    "checkType",
+    "extendsType",
+    "trueType",
+    "falseType",
+  ],
   "ContinueStatement": [
     "label",
   ],
@@ -368,6 +374,9 @@ exports[`visitor keys estree 1`] = `
     "objectType",
     "indexType",
   ],
+  "InferTypeAnnotation": [
+    "typeParameter",
+  ],
   "InferredPredicate": [],
   "InterfaceDeclaration": [
     "id",