Remove rootNodeID

We only use this to determine if something is mounted or not but I don't
think we really need to.

src/renderers/dom/fiber/ReactDOMFiberComponent.js

@@ -351,7 +351,6 @@ function trapBubbledEventsLocal() {
   var inst = this;
   // If a component renders to null or if another component fatals and causes
   // the state of the tree to be corrupted, `node` here can be null.
-  invariant(inst._rootNodeID, 'Must be mounted to trap events');
   var node = getNode(inst);
   invariant(
     node,
@@ -736,8 +735,6 @@ function updateDOMChildren(workInProgress, lastProps, nextProps, transaction, co
   }
 }
 
-var globalIdCounter = 1;
-
 var ReactDOMFiberComponent = {
 
 
@@ -763,7 +760,6 @@ var ReactDOMFiberComponent = {
     // workInProgress._tag = tag.toLowerCase();
     // setAndValidateContentChildDev.call(workInProgress, null);
 
-    workInProgress._rootNodeID = globalIdCounter++;
     workInProgress._domID = hostContainerInfo._idCounter++;
     workInProgress._hostParent = hostParent;
     workInProgress._hostContainerInfo = hostContainerInfo;
@@ -1089,7 +1085,6 @@ var ReactDOMFiberComponent = {
     workInProgress.unmountChildren(safely, skipLifecycle);
     ReactDOMComponentTree.uncacheNode(workInProgress);
     EventPluginHub.deleteAllListeners(workInProgress);
-    workInProgress._rootNodeID = 0;
     workInProgress._domID = 0;
     workInProgress._wrapperState = null;
 

src/renderers/dom/fiber/wrappers/ReactDOMFiberInput.js

@@ -256,10 +256,7 @@ var ReactDOMInput = {
   },
 
   restoreControlledState: function(inst) {
-    if (inst._rootNodeID) {
-      // DOM component is still mounted; update
-      ReactDOMInput.updateWrapper(inst);
-    }
+    ReactDOMInput.updateWrapper(inst);
     var props = inst._currentElement.props;
     updateNamedCousins(inst, props);
   },
@@ -304,9 +301,7 @@ function updateNamedCousins(thisInstance, props) {
       // If this is a controlled radio button group, forcing the input that
       // was previously checked to update will cause it to be come re-checked
       // as appropriate.
-      if (otherInstance._rootNodeID) {
-        ReactDOMInput.updateWrapper(otherInstance);
-      }
+      ReactDOMInput.updateWrapper(otherInstance);
     }
   }
 }

src/renderers/dom/fiber/wrappers/ReactDOMFiberSelect.js

@@ -187,13 +187,11 @@ var ReactDOMSelect = {
   },
 
   restoreControlledState: function(inst) {
-    if (inst._rootNodeID) {
-      var props = inst._currentElement.props;
-      var value = props.value;
+    var props = inst._currentElement.props;
+    var value = props.value;
 
-      if (value != null) {
-        updateOptions(inst, Boolean(props.multiple), value);
-      }
+    if (value != null) {
+      updateOptions(inst, Boolean(props.multiple), value);
     }
   },
 };

src/renderers/dom/fiber/wrappers/ReactDOMFiberTextarea.js

@@ -162,10 +162,8 @@ var ReactDOMTextarea = {
   },
 
   restoreControlledState: function(inst) {
-    if (inst._rootNodeID) {
-      // DOM component is still mounted; update
-      ReactDOMTextarea.updateWrapper(inst);
-    }
+    // DOM component is still mounted; update
+    ReactDOMTextarea.updateWrapper(inst);
   },
 
 };