SF: Clean up input info calculations

This CL simplifies the calculation of the input transform and frame for
Layers.

It also switches the calculations to use floats rather than intergers
for greater precesion when scaling.

Bug: 200787840
Bug: 179274888
Test: atest libgui_test
Change-Id: Ia1ed53b669caa867e5b98e72d5d71ed615222f8f
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index 9e10b4f..3fecdec 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -1093,7 +1093,7 @@
     void fillTouchOcclusionMode(gui::WindowInfo& info);
 
     // Fills in the frame and transform info for the gui::WindowInfo.
-    void fillInputFrameInfo(gui::WindowInfo&, const ui::Transform& displayTransform);
+    void fillInputFrameInfo(gui::WindowInfo&, const ui::Transform& screenToDisplay);
 
     // Cached properties computed from drawing state
     // Effective transform taking into account parent transforms and any parent scaling, which is