Fix false "unknown property" warnings for events in SSR

src/renderers/dom/shared/__tests__/ReactDOMServerIntegration-test.js

@@ -281,28 +281,47 @@ function expectMarkupMismatch(serverElement, clientElement) {
   return testMarkupMatch(serverElement, clientElement, false);
 }
 
+// TODO: this is a hack for testing dynamic injection. Remove this when we decide
+// how to do static injection instead.
+let onAfterResetModules = null;
+
 // When there is a test that renders on server and then on client and expects a logged
 // error, you want to see the error show up both on server and client. Unfortunately,
 // React refuses to issue the same error twice to avoid clogging up the console.
 // To get around this, we must reload React modules in between server and client render.
-let onAfterResetModules = null;
 function resetModules() {
+  // First, reset the modules to load the client renderer.
   jest.resetModuleRegistry();
+  if (typeof onAfterResetModules === 'function') {
+    onAfterResetModules();
+  }
+
+  // TODO: can we express this test with only public API?
+  ExecutionEnvironment = require('ExecutionEnvironment');
+
   PropTypes = require('prop-types');
   React = require('react');
   ReactDOM = require('react-dom');
-  ReactDOMServer = require('react-dom/server');
   ReactDOMFeatureFlags = require('ReactDOMFeatureFlags');
-  ReactDOMNodeStream = require('react-dom/node-stream');
   ReactTestUtils = require('react-dom/test-utils');
-  // TODO: can we express this test with only public API?
-  ExecutionEnvironment = require('ExecutionEnvironment');
 
-  // TODO: this is a hack for testing dynamic injection. Remove this when we decide
-  // how to do static injection instead.
+  // Now we reset the modules again to load the server renderer.
+  // Resetting is important because we want to avoid any shared state
+  // influencing the tests.
+  jest.resetModuleRegistry();
+  if (typeof onAfterResetModules === 'function') {
+    onAfterResetModules();
+  }
+
+  ReactDOMServer = require('react-dom/server');
+
+  // Finally, reset modules one more time before importing the stream renderer.
+  jest.resetModuleRegistry();
   if (typeof onAfterResetModules === 'function') {
     onAfterResetModules();
   }
+
+  ReactDOMNodeStream = require('react-dom/node-stream');
 }
 
 describe('ReactDOMServerIntegration', () => {

src/renderers/dom/shared/hooks/ReactDOMUnknownPropertyHook.js

@@ -67,6 +67,11 @@ if (__DEV__) {
     if (EventPluginRegistry.registrationNameModules.hasOwnProperty(name)) {
       return true;
     }
+    if (EventPluginRegistry.plugins.length === 0 && name.indexOf('on') === 0) {
+      // If no event plugins have been injected, we might be in a server environment.
+      // Don't check events in this case.
+      return true;
+    }
     warnedProperties[name] = true;
     var lowerCasedName = name.toLowerCase();