Add missing event documentation and stability tags

src/ol/layer/heatmaplayer.js

@@ -24,6 +24,7 @@ ol.layer.HeatmapLayerProperty = {
 /**
  * @constructor
  * @extends {ol.layer.Vector}
+ * @fires {@link ol.render.Event} ol.render.Event
  * @param {olx.layer.HeatmapOptions=} opt_options Options.
  * @todo stability experimental
  */

src/ol/layer/imagelayer.js

@@ -7,6 +7,7 @@ goog.require('ol.layer.Layer');
 /**
  * @constructor
  * @extends {ol.layer.Layer}
+ * @fires {@link ol.render.Event} ol.render.Event
  * @param {olx.layer.LayerOptions} options Layer options.
  * @todo stability experimental
  */

src/ol/layer/layer.js

@@ -12,6 +12,7 @@ goog.require('ol.source.Source');
 /**
  * @constructor
  * @extends {ol.layer.Base}
+ * @fires {@link ol.render.Event} ol.render.Event
  * @param {olx.layer.LayerOptions} options Layer options.
  * @todo stability experimental
  * @todo observable brightness {number} the brightness of the layer

src/ol/layer/tilelayer.js

@@ -16,6 +16,7 @@ ol.layer.TileProperty = {
 /**
  * @constructor
  * @extends {ol.layer.Layer}
+ * @fires {@link ol.render.Event} ol.render.Event
  * @param {olx.layer.TileOptions} options Tile layer options.
  * @todo stability experimental
  * @todo observable preload {number} the level to preload tiles up to

src/ol/layer/vectorlayer.js

@@ -10,6 +10,7 @@ goog.require('ol.layer.Layer');
 /**
  * @constructor
  * @extends {ol.layer.Layer}
+ * @fires {@link ol.render.Event} ol.render.Event
  * @param {olx.layer.VectorOptions=} opt_options Options.
  * @todo stability experimental
  */