asssitant: ignore server timezone and locale

Bug: b:79359468
Test: locally build and run
Change-Id: I031c85fd1aad7647b84741f638b9dac385ea560a
Reviewed-on: https://chromium-review.googlesource.com/1048121Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Xiaohui Chen <xiaohuic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#556598}

chromeos/services/assistant/platform/system_provider_impl.cc

@@ -38,5 +38,8 @@ bool SystemProviderImpl::GetBatteryState(BatteryState* state) {
   return false;
 }
 
+void SystemProviderImpl::UpdateTimezoneAndLocale(const std::string& timezone,
+                                                 const std::string& locale) {}
+
 }  // namespace assistant
 }  // namespace chromeos

chromeos/services/assistant/platform/system_provider_impl.h

@@ -23,6 +23,8 @@ class SystemProviderImpl : public assistant_client::SystemProvider {
   void RegisterMicMuteChangeCallback(ConfigChangeCallback callback) override;
   assistant_client::PowerManagerProvider* GetPowerManagerProvider() override;
   bool GetBatteryState(BatteryState* state) override;
+  void UpdateTimezoneAndLocale(const std::string& timezone,
+                               const std::string& locale) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SystemProviderImpl);