Fix lens shading map origin calculation.

Bug: 24816235
Change-Id: Id4609f3349f86c811cbc3d5e1839f880da926486
diff --git a/core/jni/android_hardware_camera2_DngCreator.cpp b/core/jni/android_hardware_camera2_DngCreator.cpp
index 8b69bbd..4faea18 100644
--- a/core/jni/android_hardware_camera2_DngCreator.cpp
+++ b/core/jni/android_hardware_camera2_DngCreator.cpp
@@ -1660,10 +1660,11 @@
         uint32_t width = static_cast<uint32_t>(entry.data.i32[2]);
         uint32_t height = static_cast<uint32_t>(entry.data.i32[3]);
         if (entry2.count > 0 && entry2.count == lsmWidth * lsmHeight * 4) {
+            // GainMap rectangle is relative to the active area origin.
             err = builder.addGainMapsForMetadata(lsmWidth,
                                                  lsmHeight,
-                                                 ymin,
-                                                 xmin,
+                                                 0,
+                                                 0,
                                                  height,
                                                  width,
                                                  opcodeCfaLayout,