Hide Config::Load method

Constructor is going to load data instead.
This makes clear that ::Load is one time operations.

Change-Id: Id7b2275544cc034d30737bea21b3d8cc68e4a8a9
Reviewed-on: https://weave-review.googlesource.com/2080
Reviewed-by: Vitaly Buka <vitalybuka@google.com>
diff --git a/src/config.cc b/src/config.cc
index 442a87a..37e907c 100644
--- a/src/config.cc
+++ b/src/config.cc
@@ -85,7 +85,9 @@
     : EnumToStringMap(kRootClientTokenOwnerMap) {}
 
 Config::Config(provider::ConfigStore* config_store)
-    : settings_{CreateDefaultSettings()}, config_store_{config_store} {}
+    : settings_{CreateDefaultSettings()}, config_store_{config_store} {
+  Load();
+}
 
 void Config::AddOnChangedCallback(const OnChangedCallback& callback) {
   on_changed_.push_back(callback);