ui/base/models: Use TreeNode::IsRoot in some obvious places.

Changes done here:
- Convert IsRoot to is_root (simple getter accessor).
- Add a simple unittest.

BUG=None
TEST=out/Debug/app_unittests --gtest_filter=TreeNodeModelTest.IsRoot

R=sky@chromium.org

Review URL: http://codereview.chromium.org/7104004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@87402 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 17 insertions, 8 deletions

diff --git a/chrome/browser/extensions/extension_bookmarks_module.cc b/chrome/browser/extensions/extension_bookmarks_module.cc
index 3e3a769..185b212 100644
--- a/chrome/browser/extensions/extension_bookmarks_module.cc
+++ b/chrome/browser/extensions/extension_bookmarks_module.cc
@@ -449,7 +449,7 @@ bool CreateBookmarkFunction::RunImpl() {
     error_ = keys::kNoParentError;
     return false;
   }
-  if (parent->parent() == NULL) {  // Can't create children of the root.
+  if (parent->is_root()) {  // Can't create children of the root.
     error_ = keys::kModifySpecialError;
     return false;
   }
@@ -705,7 +705,7 @@ class RemoveBookmarksBucketMapper : public BookmarkBucketMapper<std::string> {
     for (IdList::iterator it = ids.begin(); it != ids.end(); ++it) {
       BookmarkModel* model = profile_->GetBookmarkModel();
       const BookmarkNode* node = model->GetNodeByID(*it);
-      if (!node || !node->parent())
+      if (!node || node->is_root())
         return;
 
       std::string bucket_id;
diff --git a/chrome/browser/sync/glue/bookmark_change_processor.cc b/chrome/browser/sync/glue/bookmark_change_processor.cc
index bd0a82b..da0605c 100644
--- a/chrome/browser/sync/glue/bookmark_change_processor.cc
+++ b/chrome/browser/sync/glue/bookmark_change_processor.cc
@@ -95,7 +95,7 @@ void BookmarkChangeProcessor::RemoveSyncNodeHierarchy(
   sync_api::WriteTransaction trans(share_handle());
 
   // Later logic assumes that |topmost| has been unlinked.
-  DCHECK(!topmost->parent());
+  DCHECK(topmost->is_root());
 
   // A BookmarkModel deletion event means that |node| and all its children were
   // deleted. Sync backend expects children to be deleted individually, so we do
@@ -107,7 +107,7 @@ void BookmarkChangeProcessor::RemoveSyncNodeHierarchy(
   int index = 0;
   while (node) {
     // The top of |index_stack| should always be |node|'s index.
-    DCHECK(!node->parent() || (node->parent()->GetIndexOf(node) ==
+    DCHECK(node->is_root() || (node->parent()->GetIndexOf(node) ==
       index_stack.top()));
     if (index == node->child_count()) {
       // If we've processed all of |node|'s children, delete |node| and move
diff --git a/chrome/browser/ui/gtk/bookmarks/bookmark_editor_gtk.cc b/chrome/browser/ui/gtk/bookmarks/bookmark_editor_gtk.cc
index 2d39eac..9e0b4e7 100644
--- a/chrome/browser/ui/gtk/bookmarks/bookmark_editor_gtk.cc
+++ b/chrome/browser/ui/gtk/bookmarks/bookmark_editor_gtk.cc
@@ -67,7 +67,7 @@ class BookmarkEditorGtk::ContextMenuController
   void RunMenu(const gfx::Point& point, guint32 event_time) {
     const BookmarkNode* selected_node = GetSelectedNode();
     if (selected_node)
-      running_menu_for_root_ = selected_node->parent()->IsRoot();
+      running_menu_for_root_ = selected_node->parent()->is_root();
 #if defined(TOOLKIT_VIEWS)
     menu_->RunContextMenuAt(point);
 #else
diff --git a/ui/base/models/tree_node_model.h b/ui/base/models/tree_node_model.h
index a4509cf..254cd20 100644
--- a/ui/base/models/tree_node_model.h
+++ b/ui/base/models/tree_node_model.h
@@ -133,6 +133,9 @@ class TreeNode : public TreeModelNode {
   const NodeType* parent() const { return parent_; }
   NodeType* parent() { return parent_; }
 
+  // Returns true if this is the root node.
+  bool is_root() const { return parent_ == NULL; }
+
   // Returns the index of |node|, or -1 if |node| is not a child of this.
   int GetIndexOf(const NodeType* node) const {
     DCHECK(node);
@@ -149,9 +152,6 @@ class TreeNode : public TreeModelNode {
   // TreeModelNode:
   virtual const string16& GetTitle() const OVERRIDE { return title_; }
 
-  // Returns true if this is the root.
-  bool IsRoot() const { return parent_ == NULL; }
-
   // Returns true if this == ancestor, or one of this nodes parents is
   // ancestor.
   bool HasAncestor(const NodeType* ancestor) const {
diff --git a/ui/base/models/tree_node_model_unittest.cc b/ui/base/models/tree_node_model_unittest.cc
index acee7d0..b6097c3 100644
--- a/ui/base/models/tree_node_model_unittest.cc
+++ b/ui/base/models/tree_node_model_unittest.cc
@@ -317,4 +317,13 @@ TEST_F(TreeNodeModelTest, BasicOperations) {
   delete root;
 }
 
+TEST_F(TreeNodeModelTest, IsRoot) {
+  TreeNodeWithValue<int> root;
+  EXPECT_TRUE(root.is_root());
+
+  TreeNodeWithValue<int>* child1 = new TreeNodeWithValue<int>(1);
+  root.Add(child1, root.child_count());
+  EXPECT_FALSE(child1->is_root());
+}
+
 }  // namespace ui