Fixing window transform not changing monotonically with shift

Change-Id: I40f095e73ca1cdb994d34aecc2c6be90f3e0f25b
diff --git a/src/com/android/launcher3/Utilities.java b/src/com/android/launcher3/Utilities.java
index d559b44..31dab97 100644
--- a/src/com/android/launcher3/Utilities.java
+++ b/src/com/android/launcher3/Utilities.java
@@ -31,6 +31,7 @@
 import android.graphics.Matrix;
 import android.graphics.Paint;
 import android.graphics.Rect;
+import android.graphics.RectF;
 import android.os.Build;
 import android.os.Bundle;
 import android.os.DeadObjectException;
@@ -232,6 +233,19 @@
         return new int[] {sLoc1[0] - sLoc0[0], sLoc1[1] - sLoc0[1]};
     }
 
+    public static void scaleRectFAboutCenter(RectF r, float scale) {
+        if (scale != 1.0f) {
+            float cx = r.centerX();
+            float cy = r.centerY();
+            r.offset(-cx, -cy);
+            r.left = r.left * scale;
+            r.top = r.top * scale ;
+            r.right = r.right * scale;
+            r.bottom = r.bottom * scale;
+            r.offset(cx, cy);
+        }
+    }
+
     public static void scaleRectAboutCenter(Rect r, float scale) {
         if (scale != 1.0f) {
             int cx = r.centerX();