update_engine: Update libchrome APIS to r456626.
The new libchrome has been ported from Chromium and some APIs
have changed. Make necessary changes at call sites.
BUG=chromium:724678
CQ-DEPEND=CL:480928
Test: Build.
Change-Id: I4dbaea4a2a19031375a8bf2415645a4f226dab57
diff --git a/common/prefs_unittest.cc b/common/prefs_unittest.cc
index 73ceb00..aa2eb04 100644
--- a/common/prefs_unittest.cc
+++ b/common/prefs_unittest.cc
@@ -44,7 +44,7 @@
protected:
void SetUp() override {
ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
- prefs_dir_ = temp_dir_.path();
+ prefs_dir_ = temp_dir_.GetPath();
ASSERT_TRUE(prefs_.Init(prefs_dir_));
}