charger: support screen rotation

Bug: 191831427
Test: charging animation can show in display correctly
Signed-off-by: Jack Wu <wjack@google.com>
Change-Id: Iedcd7d6c3cd841c44bdf1116701abcbd12a26959
diff --git a/healthd/healthd_draw.h b/healthd/healthd_draw.h
index 0d7ac7a..3d4abbd 100644
--- a/healthd/healthd_draw.h
+++ b/healthd/healthd_draw.h
@@ -35,6 +35,9 @@
   // Blanks screen if true, unblanks if false.
   virtual void blank_screen(bool blank, int drm);
 
+  // Rotate screen.
+  virtual void rotate_screen(int drm);
+
   static std::unique_ptr<HealthdDraw> Create(animation *anim);
 
  protected: