[android] - add transparent image for MarkerViews ghosting SymbolAnnotations (#6675)

* [android] - add transparent image to core for MarkerView ghosting SymbolAnnotations. Removes logging messages: `Can't find sprite ... `. Cleanup MapView.

* [android] - use alpha_8 config to only allocate one byte, rename id for better readability.

1 files changed, 3 insertions, 4 deletions

diff --git a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/annotations/MarkerView.java b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/annotations/MarkerView.java
index b1008e290b..5c84fb9992 100644
--- a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/annotations/MarkerView.java
+++ b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/annotations/MarkerView.java
@@ -1,6 +1,5 @@
 package com.mapbox.mapboxsdk.annotations;
 
-import android.graphics.Bitmap;
 import android.support.annotation.FloatRange;
 import android.support.annotation.Nullable;
 
@@ -302,10 +301,10 @@ public class MarkerView extends Marker {
     @Override
     public void setIcon(@Nullable Icon icon) {
         if (icon != null) {
-            markerViewIcon = IconFactory.recreate("icon", icon.getBitmap());
+            markerViewIcon = IconFactory.recreate(IconFactory.ICON_MARKERVIEW_ID, icon.getBitmap());
         }
-        Bitmap bitmap = Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888);
-        Icon transparentIcon = IconFactory.recreate("markerViewSettings", bitmap);
+        Icon transparentIcon = IconFactory.recreate(IconFactory.ICON_MARKERVIEW_ID,
+                IconFactory.ICON_MARKERVIEW_BITMAP);
         if (markerViewManager != null) {
             markerViewManager.updateIcon(this);
         }