[android] #4335 - add clear method for removing annotations to MapboxMap

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapboxMap.java

@@ -894,6 +894,14 @@ public class MapboxMap {
         mAnnotations.clear();
     }
 
+    /**
+     * Removes all markers, polylines, polygons, overlays, etc from the map.
+     */
+    @UiThread
+    public void clear(){
+        removeAnnotations();
+    }
+
     /**
      * Return a annotation based on its id.
      *

platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/annotation/PolylineActivity.java

@@ -159,7 +159,7 @@ public class PolylineActivity extends AppCompatActivity {
             case R.id.action_id_remove:
                 // test to remove all annotations
                 mPolylineOptions.clear();
-                mMapboxMap.removeAnnotations();
+                mMapboxMap.clear();
                 return true;
 
             case android.R.id.home:

platform/android/MapboxGLAndroidSDKTestApp/src/test/java/com/mapbox/mapboxsdk/maps/MapboxMapTest.java

@@ -751,6 +751,18 @@ public class MapboxMapTest {
         assertTrue("Annotations should be empty", mMapboxMap.getAnnotations().isEmpty());
     }
 
+    @Test
+    public void testClear() {
+        List<MarkerOptions> markerList = new ArrayList<>();
+        MarkerOptions markerOptions1 = new MarkerOptions().title("a");
+        MarkerOptions markerOptions2 = new MarkerOptions().title("b");
+        markerList.add(markerOptions1);
+        markerList.add(markerOptions2);
+        mMapboxMap.addMarkers(markerList);
+        mMapboxMap.clear();
+        assertTrue("Annotations should be empty", mMapboxMap.getAnnotations().isEmpty());
+    }
+
     @Test
     public void testRemoveAnnotationsByList() {
         List<MarkerOptions> markerList = new ArrayList<>();