Fix grammatical errors in comments in ui/views

ui/views/controls/tree/tree_view_views_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/views/controls/tree/tree_view_views.h"
 
 #include <string>
 
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
@@ skipping 224 matching lines @@
 TEST_F(TreeViewViewsTest, TreeNodesRemoved) {
   // Add c1 as a child of c and c11 as a child of c1.
   Add(Add(GetNodeByTitle("c"), 0, "c1"), 0, "c11");
   tree_.SetModel(&model_);
 
   // Remove c11, which shouldn't have any effect on the tree.
   EXPECT_EQ("root [a b c]", TreeViewContentsAsString());
   EXPECT_EQ("root", GetSelectedNodeTitle());
   EXPECT_EQ(4, GetRowCount());
 
-  // Expand b1, then collapse it and remove it's only child, b1. This shouldn't
+  // Expand b1, then collapse it and remove its only child, b1. This shouldn't
   // effect the tree.
   tree_.Expand(GetNodeByTitle("b"));
   tree_.Collapse(GetNodeByTitle("b"));
   delete model_.Remove(GetNodeByTitle("b1")->parent(), GetNodeByTitle("b1"));
   EXPECT_EQ("root [a b c]", TreeViewContentsAsString());
   EXPECT_EQ("root", GetSelectedNodeTitle());
   EXPECT_EQ(4, GetRowCount());
 
   // Remove 'b'.
   delete model_.Remove(GetNodeByTitle("b")->parent(), GetNodeByTitle("b"));
@@ skipping 119 matching lines @@
   EXPECT_EQ("b", GetSelectedNodeTitle());
   ExpandOrSelectChild();
   EXPECT_EQ("root [a b [b1] c]", TreeViewContentsAsString());
   EXPECT_EQ("b1", GetSelectedNodeTitle());
   ExpandOrSelectChild();
   EXPECT_EQ("root [a b [b1] c]", TreeViewContentsAsString());
   EXPECT_EQ("b1", GetSelectedNodeTitle());
 }
 
 }  // namespace views