installer and some misc files: Change ScopedTempDir::path() to GetPath()

path() is being deprecated, GetPath() has better checking against wrong use.

For more context, see https://codereview.chromium.org/2275553005/.

BUG=640599

Review-Url: https://codereview.chromium.org/2379543002
Cr-Commit-Position: refs/heads/master@{#422068}
diff --git a/components/prefs/json_pref_store_unittest.cc b/components/prefs/json_pref_store_unittest.cc
index f6ce3ad..99f12a73 100644
--- a/components/prefs/json_pref_store_unittest.cc
+++ b/components/prefs/json_pref_store_unittest.cc
@@ -1081,7 +1081,7 @@
  protected:
   void SetUp() override {
     JsonPrefStoreTest::SetUp();
-    test_file_ = temp_dir_.path().AppendASCII("test.json");
+    test_file_ = temp_dir_.GetPath().AppendASCII("test.json");
   }
 
   scoped_refptr<JsonPrefStore> CreatePrefStore() {
@@ -1251,4 +1251,4 @@
             write_callback_observer_.GetAndResetPostWriteObservationState());
 }
 
-}  // namespace base
\ No newline at end of file
+}  // namespace base