Fixed dumb bug that caused grid sampling to sample 2x too wide in the horizontal direction.

git-svn-id: https://zxing.googlecode.com/svn/trunk@7 59b500cc-1b3d-0410-9834-0bbf25fbcc57
diff --git a/core/src/com/google/zxing/qrcode/detector/DefaultGridSampler.java b/core/src/com/google/zxing/qrcode/detector/DefaultGridSampler.java
index 86853e0..a836cbe 100644
--- a/core/src/com/google/zxing/qrcode/detector/DefaultGridSampler.java
+++ b/core/src/com/google/zxing/qrcode/detector/DefaultGridSampler.java
@@ -67,7 +67,7 @@
       int max = points.length;
       float iValue = (float) i + 0.5f;
       for (int j = 0; j < max; j += 2) {
-        points[j] = (float) j + 0.5f;
+        points[j] = (float) (j >> 1) + 0.5f;
         points[j + 1] = iValue;
       }
       transform.transform(points);