Convert orientation values in input to ui::Rotation.

ui::Rotation both provides better typesafety as well as some convenience
functions (e.g. operator+, operator-).

Test: atest TouchVideoFrame_test.cpp InputReader_test.cpp
Change-Id: Ib423457c742ed3d41f2e3fc269ddf86809cbf247
diff --git a/include/input/Input.h b/include/input/Input.h
index d298d81..07a566a 100644
--- a/include/input/Input.h
+++ b/include/input/Input.h
@@ -577,7 +577,7 @@
 
     inline const ui::Transform& getTransform() const { return mTransform; }
 
-    int getSurfaceRotation() const;
+    int32_t getSurfaceRotation() const;
 
     inline float getXPrecision() const { return mXPrecision; }