Support mixed props for components

Summary:
Changelog:
[Changed][General] - Support mixed props for components in codegen

Reviewed By: rickhanlonii

Differential Revision: D43894460

fbshipit-source-id: e5faf2f83e6829170cdce550e923c3c09ddff0b0

packages/react-native-codegen/src/generators/components/GeneratePropsJavaPojo/PojoCollector.js

@@ -20,6 +20,7 @@ import type {
   FloatTypeAnnotation,
   Int32TypeAnnotation,
   PropTypeAnnotation,
+  MixedTypeAnnotation,
 } from '../../../CodegenSchema';
 
 const {capitalize} = require('../../Utils');
@@ -89,7 +90,8 @@ export type PojoTypeAnnotation =
             type: 'ArrayTypeAnnotation',
             elementType: PojoTypeAliasAnnotation,
           }>,
-    }>;
+    }>
+  | MixedTypeAnnotation;
 
 class PojoCollector {
   _pojos: Map<string, Pojo> = new Map();

packages/react-native-codegen/src/generators/components/GeneratePropsJavaPojo/serializePojo.js

@@ -24,6 +24,7 @@ function toJavaType(
     addImport('com.facebook.react.bridge.ReadableMap');
   const importArrayList = () => addImport('java.util.ArrayList');
   const importYogaValue = () => addImport('com.facebook.yoga.YogaValue');
+  const importDynamic = () => addImport('com.facebook.react.bridge.Dynamic');
   switch (typeAnnotation.type) {
     /**
      * Primitives
@@ -222,6 +223,11 @@ function toJavaType(
       return `ArrayList<${elementTypeString}>`;
     }
 
+    case 'MixedTypeAnnotation': {
+      importDynamic();
+      return 'Dynamic';
+    }
+
     default: {
       (typeAnnotation.type: empty);
       throw new Error(