Fix drag and drop (2/3)

Handle InputWindowCommands in SurfaceFlinger. Send transferTouchFocus from
SurfaceFlinger to InputFlinger.

Test: InputSurfacesTest.transfer_touch_focus
Bug: 120463595
Change-Id: I6592cc9ee4a77700ea191fd1ca337b91895b61fe
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index bfc87a0..38c2fda 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -543,6 +543,7 @@
     void handleTransactionLocked(uint32_t transactionFlags);
 
     void updateInputWindows();
+    void executeInputWindowCommands();
     void updateCursorAsync();
 
     /* handlePageFlip - latch a new buffer if available and compute the dirty