recovery: Get UI and locale from device.

This removes some reliance on the global
locale and ui variables.

Test: Recovery works
Bug: 78793464
Change-Id: I78f1a2b321f5d50aa58b10735a73ae137283353a
diff --git a/ui.h b/ui.h
index 35cc36e..f867790 100644
--- a/ui.h
+++ b/ui.h
@@ -57,6 +57,8 @@
   // the given locale. Returns true on success.
   virtual bool Init(const std::string& locale);
 
+  virtual std::string GetLocale() = 0;
+
   // Shows a stage indicator. Called immediately after Init().
   virtual void SetStage(int current, int max) = 0;