Add support for calibrating touch position.

Useful for tweaking touch screen alignment without having to modify the
kernel device driver x/y axis bounds.

Change-Id: I6ca43d3c138548f9dfb76aa33150a0c853698fb6
diff --git a/include/ui/InputReader.h b/include/ui/InputReader.h
index eb88d8b..2d4bf8b 100644
--- a/include/ui/InputReader.h
+++ b/include/ui/InputReader.h
@@ -584,6 +584,16 @@
 
     // Immutable calibration parameters in parsed form.
     struct Calibration {
+        // Position
+        bool haveXOrigin;
+        int32_t xOrigin;
+        bool haveYOrigin;
+        int32_t yOrigin;
+        bool haveXScale;
+        float xScale;
+        bool haveYScale;
+        float yScale;
+
         // Touch Size
         enum TouchSizeCalibration {
             TOUCH_SIZE_CALIBRATION_DEFAULT,