Set the default value for align items as stretch (#189)

flexbox/src/androidTest/java/com/google/android/flexbox/test/FlexboxLayoutManagerTest.java

@@ -1709,6 +1709,7 @@ public class FlexboxLayoutManagerTest {
                 activity.setContentView(R.layout.recyclerview);
                 RecyclerView recyclerView = (RecyclerView) activity.findViewById(R.id.recyclerview);
                 layoutManager.setFlexDirection(FlexDirection.ROW);
+                layoutManager.setAlignItems(AlignItems.FLEX_START);
                 recyclerView.setLayoutManager(layoutManager);
                 recyclerView.setAdapter(adapter);
                 for (int i = 0; i < 50; i++) {
@@ -1767,6 +1768,7 @@ public class FlexboxLayoutManagerTest {
                 activity.setContentView(R.layout.recyclerview);
                 RecyclerView recyclerView = (RecyclerView) activity.findViewById(R.id.recyclerview);
                 layoutManager.setFlexDirection(FlexDirection.COLUMN);
+                layoutManager.setAlignItems(AlignItems.FLEX_START);
                 recyclerView.setLayoutManager(layoutManager);
                 recyclerView.setAdapter(adapter);
                 for (int i = 0; i < 50; i++) {

flexbox/src/main/java/com/google/android/flexbox/FlexboxLayoutManager.java

@@ -168,6 +168,7 @@ public class FlexboxLayoutManager extends RecyclerView.LayoutManager implements
             @FlexWrap int flexWrap) {
         setFlexDirection(flexDirection);
         setFlexWrap(flexWrap);
+        setAlignItems(AlignItems.STRETCH);
         setAutoMeasureEnabled(true);
     }
 
@@ -204,8 +205,8 @@ public class FlexboxLayoutManager extends RecyclerView.LayoutManager implements
                 }
                 break;
         }
-
         setFlexWrap(FlexWrap.WRAP);
+        setAlignItems(AlignItems.STRETCH);
         setAutoMeasureEnabled(true);
     }