fix(FitBounds): remove old location on loc change (#1710)

when a FitBoundsAccessor emits new bounds,  remove the old ones from
the map's bounds array

fixes: #1512

packages/core/directives/fit-bounds.ts

@@ -3,7 +3,6 @@ import { Subscription, Subject } from 'rxjs';
 import { distinctUntilChanged, takeUntil } from 'rxjs/operators';
 
 import { FitBoundsService, FitBoundsAccessor, FitBoundsDetails } from '../services/fit-bounds';
-import { LatLng, LatLngLiteral } from '../services/google-maps-types';
 
 /**
  * Adds the given directive to the auto fit bounds feature when the value is true.
@@ -53,17 +52,29 @@ export class AgmFitBounds implements OnInit, OnDestroy, OnChanges {
  .subscribe(details => this._updateBounds(details));
  }
 
+ /*
+ Either the location changed, or visible status changed.
+ Possible state changes are
+ invisible -> visible
+ visible -> invisible
+ visible -> visible (new location)
+ */
  private _updateBounds(newFitBoundsDetails?: FitBoundsDetails) {
+ // either visibility will change, or location, so remove the old one anyway
+ if (this._latestFitBoundsDetails) {
+ this._fitBoundsService.removeFromBounds(this._latestFitBoundsDetails.latLng);
+ // don't set latestFitBoundsDetails to null, because we can toggle visibility from
+ // true -> false -> true, in which case we still need old value cached here
+ }
+
  if (newFitBoundsDetails) {
  this._latestFitBoundsDetails = newFitBoundsDetails;
  }
  if (!this._latestFitBoundsDetails) {
  return;
  }
- if (this.agmFitBounds) {
+ if (this.agmFitBounds === true) {
  this._fitBoundsService.addToBounds(this._latestFitBoundsDetails.latLng);
- } else {
- this._fitBoundsService.removeFromBounds(this._latestFitBoundsDetails.latLng);
  }
  }