hwc: Add binder interface to get the visibleRegion

- This binder interface can be used by clients to know the
  active visible region for a display(pri/ext/virt)
- When external orientation is used, return the destFrame of
  the FrameBuffer layer, as its the viewFrame

Change-Id: I7cfd149c76c16b9a3031103c89b1932d44bcbecd
diff --git a/libqservice/IQService.h b/libqservice/IQService.h
index d6e525a..f8e58ab 100644
--- a/libqservice/IQService.h
+++ b/libqservice/IQService.h
@@ -48,6 +48,7 @@
         CHECK_EXTERNAL_STATUS,   // Check status of external display
         GET_DISPLAY_ATTRIBUTES,  // Get display attributes
         SET_HSIC_DATA,           // Set HSIC on dspp
+        GET_DISPLAY_VISIBLE_REGION,  // Get the visibleRegion for dpy
         VPU_COMMAND_LIST_START = 100, //Reserved block for VPU commands
         VPU_COMMAND_LIST_END   = 200,
         COMMAND_LIST_END = 400,