Change FeatureLayer, no longer extend / shrink layerBounds as features

are added. 

Pass layerBounds to M.featureLayer initialize via option during 
initialization; use M.getBounds(mapml) to derive bounds from map-meta 
in the MapMLLayer._content (in the case of MapMLLayer._mapmlvectors),
pass the derived bounds (from TemplatedFeaturesLayer.extentBounds and
TemplatedTileLayer.extentBounds) when creating a FeatureLayer in those
contexts. (templated layers' extentBounds property is derived from
their child map-input axis min/max values, with the M._extractInputBounds
utility).

Author: prushfor

src/mapml/layers/FeatureLayer.js

@@ -58,7 +58,9 @@ export var FeatureLayer = L.FeatureGroup.extend({
       this.addData(mapml, native.cs, native.zoom);
     } else if (!mapml) {
       this.isVisible = false;
-      this.bounds = this.options.bounds ? this.options.bounds : null;
+      this.layerBounds = this.options.layerBounds
+        ? this.options.layerBounds
+        : null;
       this.zoomBounds = this.options.zoomBounds;
     }
   },
@@ -278,16 +280,6 @@ export var FeatureLayer = L.FeatureGroup.extend({
     }
 
     let layer = this.geometryToLayer(mapml, options, nativeCS, +zoom, title);
-    if (!this.options.extent) {
-      let ext = mapml.extent,
-        xmin = ext.topLeft.pcrs.horizontal,
-        ymin = ext.bottomRight.pcrs.vertical,
-        xmax = ext.bottomRight.pcrs.horizontal,
-        ymax = ext.topLeft.pcrs.vertical,
-        bnd = L.bounds(L.point(xmin, ymin), L.point(xmax, ymax));
-
-      this.layerBounds = this.layerBounds ? this.layerBounds.extend(bnd) : bnd;
-    }
     if (layer) {
       // if the layer is being used as a query handler output, it will have
       // a color option set.  Otherwise, copy classes from the feature

src/mapml/layers/MapMLLayer.js

@@ -1515,6 +1515,7 @@ export var MapMLLayer = L.Layer.extend({
           pane: layer._container,
           opacity: layer.options.opacity,
           projection: layer._properties.projection,
+          layerBounds: M.getBounds(layer._content),
           // by NOT passing options.extent, we are asking the FeatureLayer
           // to dynamically update its .layerBounds property as features are
           // added or removed from it

src/mapml/layers/TemplatedFeaturesLayer.js

@@ -35,8 +35,8 @@ export var TemplatedFeaturesLayer = L.Layer.extend({
         // pass the vector layer the container for the parent into which
         // it will append its own container for rendering into
         pane: container,
-        // the extent will be static, fixed, constant for the lifetime of the layer
-        bounds: this.extentBounds,
+        // the bounds will be static, fixed, constant for the lifetime of the layer
+        layerBounds: this.extentBounds,
         opacity: opacity,
         projection: map.options.projection,
         static: true,

src/mapml/layers/TemplatedTileLayer.js

@@ -166,7 +166,7 @@ export var TemplatedTileLayer = L.TileLayer.extend({
     let tileFeatures = M.featureLayer(null, {
       projection: this._map.options.projection,
       static: false,
-      bounds: this.extentBounds,
+      layerBounds: this.extentBounds,
       interactive: false
     });