Change drag_drop_layout for ldpi devices

Device resolution 240x320, density 120.
DragDropActivity's child views cannot show compoletely in this
ldpi device, because in the layout file, margin is set to constant
value.
Change margin value, the case pass.

reference:
  https://android-review.googlesource.com/c/platform/cts/+/700304
Bug: 120586955
Test: android.view.cts.DragDropTest

Change-Id: I13b9b583ef2c1a2745d43f8c912837f99face4b2
diff --git a/tests/tests/view/res/layout/drag_drop_layout.xml b/tests/tests/view/res/layout/drag_drop_layout.xml
index cf882bd..9f4614c 100644
--- a/tests/tests/view/res/layout/drag_drop_layout.xml
+++ b/tests/tests/view/res/layout/drag_drop_layout.xml
@@ -25,26 +25,26 @@
             android:id="@+id/container"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:layout_margin="42dp"
+            android:layout_margin="21dp"
             android:background="#BBBBBB">
         <FrameLayout
                 android:id="@+id/subcontainer"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                android:layout_margin="42dp"
+                android:layout_margin="21dp"
                 android:background="#666666">
             <View
                     android:id="@+id/inner"
-                    android:layout_width="42dp"
-                    android:layout_height="42dp"
-                    android:layout_margin="42dp"
+                    android:layout_width="21dp"
+                    android:layout_height="21dp"
+                    android:layout_margin="21dp"
                     android:background="#00FF00" />
         </FrameLayout>
     </FrameLayout>
     <View
             android:id="@+id/draggable"
-            android:layout_width="42dp"
-            android:layout_height="42dp"
-            android:layout_margin="42dp"
+            android:layout_width="21dp"
+            android:layout_height="21dp"
+            android:layout_margin="21dp"
             android:background="#0000FF" />
 </LinearLayout>