big refactoring.

- move implementation of dev-only modules under a __DEV__ block. this ensures good DCE result for webpack/browserify users and FB's packager.
- an explicit 'Dev' postfix is added to their module names

modules renamed:
- ReactElementValidator.js -> ReactElementValidatorDev.js
- ReactComponentTreeDevtool.js -> ReactComponentTreeDevtoolDev.js
- validateDOMNesting.js -> validateDOMNestingDev.js
- ReactDOMDebugTool.js -> ReactDOMDebugToolDev.js
- ReactDOMNullInputValuePropDevtool.js -> ReactDOMNullInputValuePropDevtoolDev.js
- ReactDOMUnknownPropertyDevtool.js -> ReactDOMUnknownPropertyDevtoolDev.js
- ReactDebugTool.js -> ReactDebugToolDev.js
- ReactInstrumentation.js -> ReactInstrumentationDev.js
- ReactPerf.js -> ReactPerfDev.js
- ReactChildrenMutationWarningDevtool.js -> ReactChildrenMutationWarningDevtoolDev.js
- ReactHostOperationHistoryDevtool.js -> ReactHostOperationHistoryDevtoolDev.js
- ReactInvalidSetStateWarningDevTool.js -> ReactInvalidSetStateWarningDevToolDev.js
- canDefineProperty.js -> canDefinePropertyDev.js

Author: Keyan Zhang

src/addons/ReactWithAddons.js

@@ -17,7 +17,7 @@ var ReactComponentWithPureRenderMixin =
   require('ReactComponentWithPureRenderMixin');
 var ReactCSSTransitionGroup = require('ReactCSSTransitionGroup');
 var ReactFragment = require('ReactFragment');
-var ReactPerf = require('ReactPerf');
+var ReactPerfDev = require('ReactPerfDev');
 var ReactTestUtils = require('ReactTestUtils');
 var ReactTransitionGroup = require('ReactTransitionGroup');
 
@@ -36,7 +36,7 @@ React.addons = {
 };
 
 if (__DEV__) {
-  React.addons.Perf = ReactPerf;
+  React.addons.Perf = ReactPerfDev;
   React.addons.TestUtils = ReactTestUtils;
 }
 

src/isomorphic/React.js

@@ -17,7 +17,7 @@ var ReactPureComponent = require('ReactPureComponent');
 var ReactClass = require('ReactClass');
 var ReactDOMFactories = require('ReactDOMFactories');
 var ReactElement = require('ReactElement');
-var ReactElementValidator = require('ReactElementValidator');
+var ReactElementValidatorDev = require('ReactElementValidatorDev');
 var ReactPropTypes = require('ReactPropTypes');
 var ReactVersion = require('ReactVersion');
 
@@ -29,9 +29,9 @@ var createFactory = ReactElement.createFactory;
 var cloneElement = ReactElement.cloneElement;
 
 if (__DEV__) {
-  createElement = ReactElementValidator.createElement;
-  createFactory = ReactElementValidator.createFactory;
-  cloneElement = ReactElementValidator.cloneElement;
+  createElement = ReactElementValidatorDev.createElement;
+  createFactory = ReactElementValidatorDev.createFactory;
+  cloneElement = ReactElementValidatorDev.cloneElement;
 }
 
 var __spread = Object.assign;

src/isomorphic/classic/element/ReactDOMFactories.js

@@ -12,7 +12,7 @@
 'use strict';
 
 var ReactElement = require('ReactElement');
-var ReactElementValidator = require('ReactElementValidator');
+var ReactElementValidatorDev = require('ReactElementValidatorDev');
 
 var mapObject = require('mapObject');
 
@@ -24,7 +24,7 @@ var mapObject = require('mapObject');
  */
 function createDOMFactory(tag) {
   if (__DEV__) {
-    return ReactElementValidator.createFactory(tag);
+    return ReactElementValidatorDev.createFactory(tag);
   }
   return ReactElement.createFactory(tag);
 }

src/isomorphic/classic/element/ReactElement.js

@@ -14,7 +14,7 @@
 var ReactCurrentOwner = require('ReactCurrentOwner');
 
 var warning = require('warning');
-var canDefineProperty = require('canDefineProperty');
+var canDefinePropertyDev = require('canDefinePropertyDev');
 var hasOwnProperty = Object.prototype.hasOwnProperty;
 
 // The Symbol used to tag the ReactElement type. If there is no native Symbol
@@ -103,7 +103,7 @@ var ReactElement = function(type, key, ref, self, source, owner, props) {
     // the validation flag non-enumerable (where possible, which should
     // include every environment we run tests in), so the test framework
     // ignores it.
-    if (canDefineProperty) {
+    if (canDefinePropertyDev) {
       Object.defineProperty(element._store, 'validated', {
         configurable: false,
         enumerable: false,