Fix issue facebook#21065 getInspectorDataForViewTag is not a function (…

…facebook#21237)

Summary:
Fix renderer.getInspectorDataForViewTag is not a function when try Toggle Inspector

Fixes facebook#21065

Release Notes:
--------------
[BUGFIX] [MINOR] [/react-native/Libraries/Inspector/Inspector.js]
Pull Request resolved: facebook#21237

Differential Revision: D13838339

Pulled By: cpojer

fbshipit-source-id: 363a4beba211e7868395578c7941cbda119bc753

Libraries/Inspector/Inspector.js

@@ -47,14 +47,20 @@ function findRenderers(): $ReadOnlyArray<ReactRenderer> {
 function getInspectorDataForViewTag(touchedViewTag: number) {
   for (let i = 0; i < renderers.length; i++) {
     const renderer = renderers[i];
-    const inspectorData = renderer.getInspectorDataForViewTag(touchedViewTag);
-    if (inspectorData.hierarchy.length > 0) {
-      return inspectorData;
+    if (
+      Object.prototype.hasOwnProperty.call(
+        renderer,
+        'getInspectorDataForViewTag',
+      )
+    ) {
+      const inspectorData = renderer.getInspectorDataForViewTag(touchedViewTag);
+      if (inspectorData.hierarchy.length > 0) {
+        return inspectorData;
+      }
     }
   }
   throw new Error('Expected to find at least one React renderer.');
 }
-
 class Inspector extends React.Component<
   {
     inspectedViewTag: ?number,