Revert "Set elevation 0 when creating TopBar"

This reverts commit 05dacbd072.

lib/android/app/src/main/java/com/reactnativenavigation/viewcontrollers/topbar/TopBarController.java

 package com.reactnativenavigation.viewcontrollers.topbar;
 
 import android.content.Context;
-import android.os.Build;
 import android.support.v4.view.ViewPager;
 import android.view.View;
 
 
 
 public class TopBarController {
-    private static final int INITIAL_ELEVATION = 0;
     private TopBar topBar;
 
     public View createView(Context context, StackLayout stackLayout) {
         if (topBar == null) {
             topBar = createTopBar(context, stackLayout);
             topBar.setId(CompatUtils.generateViewId());
-            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) topBar.setElevation(INITIAL_ELEVATION);
         }
         return topBar;
     }

lib/android/app/src/test/java/com/reactnativenavigation/viewcontrollers/TopBarControllerTest.java

 
 import android.app.Activity;
 import android.content.Context;
+import android.support.annotation.NonNull;
 
 import com.reactnativenavigation.BaseTest;
 import com.reactnativenavigation.viewcontrollers.topbar.TopBarController;
 public class TopBarControllerTest extends BaseTest {
 
     private TopBarController uut;
-    private TitleBar titleBar;
-    private TopBar topBar;
-    private Activity activity;
 
     @Override
     public void beforeEach() {
-        activity = newActivity();
+        uut = new TopBarController();
+    }
+
+    @Test
+    public void clear() {
+        final TitleBar[] titleBar = new TitleBar[1];
         uut = new TopBarController() {
+            @NonNull
             @Override
             protected TopBar createTopBar(Context context, StackLayout stackLayout) {
-                topBar = spy(new TopBar(context, stackLayout) {
+                return new TopBar(context, stackLayout) {
                     @Override
                     protected TitleBar createTitleBar(Context context) {
-                        titleBar = spy(super.createTitleBar(context));
-                        return titleBar;
+                        titleBar[0] = spy(super.createTitleBar(context));
+                        return titleBar[0];
                     }
-                });
-                return topBar;
+                };
             }
         };
-    }
-
-    @Test
-    public void createView_setElevationToCancelDefaultElevationAnimationWhichMightConflictWithElevationValueFromDefaultOptions() {
-        uut.createView(activity, Mockito.mock(StackLayout.class));
-        verify(topBar).setElevation(0);
-    }
-
-    @Test
-    public void clear() {
+        Activity activity = newActivity();
         uut.createView(activity, Mockito.mock(StackLayout.class));
         uut.clear();
-        verify(titleBar, times(1)).clear();
+        verify(titleBar[0], times(1)).clear();
     }
 }