[SyncFS] Use dedicated temporary directory in LocalFileChangeTrackerTest

TEST=unit_tests --gtest_filter="LocalFileChangeTracker.*"

Review URL: https://codereview.chromium.org/391653002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@282938 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/sync_file_system/local/local_file_change_tracker_unittest.cc

@@ -45,8 +45,9 @@ class LocalFileChangeTrackerTest : public testing::Test {
   virtual void SetUp() OVERRIDE {
     file_system_.SetUp(CannedSyncableFileSystem::QUOTA_ENABLED);
 
+    ASSERT_TRUE(base_dir_.CreateUniqueTempDir());
     sync_context_ =
-        new LocalFileSyncContext(base::FilePath(),
+        new LocalFileSyncContext(base_dir_.path(),
                                  in_memory_env_.get(),
                                  base::ThreadTaskRunnerHandle::Get().get(),
                                  base::ThreadTaskRunnerHandle::Get().get());
@@ -110,6 +111,7 @@ class LocalFileChangeTrackerTest : public testing::Test {
   }
 
   base::MessageLoopForIO message_loop_;
+  base::ScopedTempDir base_dir_;
   scoped_ptr<leveldb::Env> in_memory_env_;
   CannedSyncableFileSystem file_system_;
 

chrome/browser/sync_file_system/local/local_file_sync_context.cc

@@ -56,6 +56,7 @@ LocalFileSyncContext::LocalFileSyncContext(
       shutdown_on_ui_(false),
       shutdown_on_io_(false),
       mock_notify_changes_duration_in_sec_(-1) {
+  DCHECK(base_path.IsAbsolute());
   DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
 }