don't validate propTypes in production

Switch to warnings so code execution doesn't differ between prod and
dev.

src/classic/class/ReactClass.js

@@ -327,11 +327,13 @@ var RESERVED_SPEC_KEYS = {
     }
   },
   childContextTypes: function(Constructor, childContextTypes) {
-    validateTypeDef(
-      Constructor,
-      childContextTypes,
-      ReactPropTypeLocations.childContext
-    );
+    if (__DEV__) {
+      validateTypeDef(
+        Constructor,
+        childContextTypes,
+        ReactPropTypeLocations.childContext
+      );
+    }
     Constructor.childContextTypes = assign(
       {},
       Constructor.childContextTypes,
@@ -339,11 +341,13 @@ var RESERVED_SPEC_KEYS = {
     );
   },
   contextTypes: function(Constructor, contextTypes) {
-    validateTypeDef(
-      Constructor,
-      contextTypes,
-      ReactPropTypeLocations.context
-    );
+    if (__DEV__) {
+      validateTypeDef(
+        Constructor,
+        contextTypes,
+        ReactPropTypeLocations.context
+      );
+    }
     Constructor.contextTypes = assign(
       {},
       Constructor.contextTypes,
@@ -365,11 +369,13 @@ var RESERVED_SPEC_KEYS = {
     }
   },
   propTypes: function(Constructor, propTypes) {
-    validateTypeDef(
-      Constructor,
-      propTypes,
-      ReactPropTypeLocations.prop
-    );
+    if (__DEV__) {
+      validateTypeDef(
+        Constructor,
+        propTypes,
+        ReactPropTypeLocations.prop
+      );
+    }
     Constructor.propTypes = assign(
       {},
       Constructor.propTypes,
@@ -384,7 +390,9 @@ var RESERVED_SPEC_KEYS = {
 function validateTypeDef(Constructor, typeDef, location) {
   for (var propName in typeDef) {
     if (typeDef.hasOwnProperty(propName)) {
-      invariant(
+      // use a warning instead of an invariant so components
+      // don't show up in prod but not in __DEV__
+      warning(
         typeof typeDef[propName] === 'function',
         '%s: %s type `%s` is invalid; it must be a function, usually from ' +
         'React.PropTypes.',

src/classic/class/__tests__/ReactClass-test.js

@@ -74,8 +74,11 @@ describe('ReactClass-spec', function() {
       .toBe(propValidator);
   });
 
-  it('should throw on invalid prop types', function() {
-    expect(function() {
+  it('should warn on invalid prop types', function() {
+    var warn = console.warn;
+    console.warn = mocks.getMockFunction();
+    try {
+
       React.createClass({
         displayName: 'Component',
         propTypes: {
@@ -85,14 +88,20 @@ describe('ReactClass-spec', function() {
           return <span>{this.props.prop}</span>;
         }
       });
-    }).toThrow(
-      'Invariant Violation: Component: prop type `prop` is invalid; ' +
-      'it must be a function, usually from React.PropTypes.'
-    );
+      expect(console.warn.mock.calls.length).toBe(1);
+      expect(console.warn.mock.calls[0][0]).toBe(
+        'Warning: Component: prop type `prop` is invalid; ' +
+        'it must be a function, usually from React.PropTypes.'
+      );
+    } finally {
+      console.warn = warn;
+    }
   });
 
-  it('should throw on invalid context types', function() {
-    expect(function() {
+  it('should warn on invalid context types', function() {
+    var warn = console.warn;
+    console.warn = mocks.getMockFunction();
+    try {
       React.createClass({
         displayName: 'Component',
         contextTypes: {
@@ -102,14 +111,20 @@ describe('ReactClass-spec', function() {
           return <span>{this.props.prop}</span>;
         }
       });
-    }).toThrow(
-      'Invariant Violation: Component: context type `prop` is invalid; ' +
-      'it must be a function, usually from React.PropTypes.'
-    );
+      expect(console.warn.mock.calls.length).toBe(1);
+      expect(console.warn.mock.calls[0][0]).toBe(
+        'Warning: Component: context type `prop` is invalid; ' +
+        'it must be a function, usually from React.PropTypes.'
+      );
+    } finally {
+      console.warn = warn;
+    }
   });
 
   it('should throw on invalid child context types', function() {
-    expect(function() {
+    var warn = console.warn;
+    console.warn = mocks.getMockFunction();
+    try {
       React.createClass({
         displayName: 'Component',
         childContextTypes: {
@@ -119,10 +134,14 @@ describe('ReactClass-spec', function() {
           return <span>{this.props.prop}</span>;
         }
       });
-    }).toThrow(
-      'Invariant Violation: Component: child context type `prop` is invalid; ' +
-      'it must be a function, usually from React.PropTypes.'
-    );
+      expect(console.warn.mock.calls.length).toBe(1);
+      expect(console.warn.mock.calls[0][0]).toBe(
+        'Warning: Component: child context type `prop` is invalid; ' +
+        'it must be a function, usually from React.PropTypes.'
+      );
+    } finally {
+      console.warn = warn;
+    }
   });
 
   it('should warn when mispelling shouldComponentUpdate', function() {

src/classic/element/ReactElementValidator.js

@@ -381,13 +381,15 @@ var ReactElementValidator = {
         element
       );
       var name = componentClass.displayName || componentClass.name;
-      if (componentClass.propTypes) {
-        checkPropTypes(
-          name,
-          componentClass.propTypes,
-          element.props,
-          ReactPropTypeLocations.prop
-        );
+      if (__DEV__) {
+        if (componentClass.propTypes) {
+          checkPropTypes(
+            name,
+            componentClass.propTypes,
+            element.props,
+            ReactPropTypeLocations.prop
+          );
+        }
       }
       if (typeof componentClass.getDefaultProps === 'function') {
         warning(