Split BrowserThread into public API and private implementation, step 1.

chrome/browser/bookmarks/recently_used_folders_combo_model_unittest.cc

Index: chrome/browser/bookmarks/recently_used_folders_combo_model_unittest.cc
diff --git a/chrome/browser/bookmarks/recently_used_folders_combo_model_unittest.cc b/chrome/browser/bookmarks/recently_used_folders_combo_model_unittest.cc
index d539d8af52e01be6eb628fcb9a4fb330361cd24f..ebbb213f980f2b671a3274b180fe23e6ecca1b5e 100644
--- a/chrome/browser/bookmarks/recently_used_folders_combo_model_unittest.cc
+++ b/chrome/browser/bookmarks/recently_used_folders_combo_model_unittest.cc
@@ -7,7 +7,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/test/base/testing_profile.h"
-#include "content/browser/browser_thread.h"
+#include "content/test/test_browser_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 class RecentlyUsedFoldersComboModelTest : public testing::Test {
@@ -22,8 +22,8 @@ class RecentlyUsedFoldersComboModelTest : public testing::Test {
 
  private:
   MessageLoopForUI message_loop_;
-  BrowserThread ui_thread_;
-  BrowserThread file_thread_;
+  content::TestBrowserThread ui_thread_;
+  content::TestBrowserThread file_thread_;
 
   DISALLOW_COPY_AND_ASSIGN(RecentlyUsedFoldersComboModelTest);
 };