goog.require('ol.Collection');
goog.require('ol.Coordinate');
goog.require('ol.Map');
goog.require('ol.Projection');
goog.require('ol.RendererHint');
goog.require('ol.control.Attribution');
goog.require('ol.layer.BingMaps');
goog.require('ol.layer.TileJSON');


var layers = new ol.Collection([
  new ol.layer.BingMaps(
      ol.BingMapsStyle.AERIAL,
      'AheP841R-MsLErKQChaTba_xDoOCl40-EeTubD9uNhNAyQTePwFY9iVD1_pyqqlE'),
  new ol.layer.TileJSON(
      'http://api.tiles.mapbox.com/v3/mapbox.va-quake-aug.jsonp')
]);

var webglMap = new ol.Map(document.getElementById('webglMap'), {
  center: ol.Projection.transformWithCodes(
      new ol.Coordinate(-77.93254999999999, 37.9555),
      'EPSG:4326', 'EPSG:3857'),
  layers: layers,
  renderer: ol.RendererHint.WEBGL,
  zoom: 5
});

var domMap = new ol.Map(document.getElementById('domMap'), {
  renderer: ol.RendererHint.DOM
});
domMap.bindTo('center', webglMap);
domMap.bindTo('layers', webglMap);
domMap.bindTo('resolution', webglMap);
domMap.bindTo('rotation', webglMap);

var attributionControl = new ol.control.Attribution(webglMap);
document.getElementById('attribution').appendChild(
    attributionControl.getElement());

goog.require('ol.Collection');
goog.require('ol.Coordinate');
goog.require('ol.Map');
goog.require('ol.Projection');
goog.require('ol.RendererHint');
goog.require('ol.control.Attribution');
goog.require('ol.layer.BingMaps');
goog.require('ol.layer.TileJSON');


var layers = new ol.Collection([
  new ol.layer.BingMaps(
      ol.BingMapsStyle.AERIAL,
      'AheP841R-MsLErKQChaTba_xDoOCl40-EeTubD9uNhNAyQTePwFY9iVD1_pyqqlE'),
  new ol.layer.TileJSON(
      'http://api.tiles.mapbox.com/v3/mapbox.va-quake-aug.jsonp')
]);

var webglMap = new ol.Map(document.getElementById('webglMap'), {
  center: ol.Projection.transformWithCodes(
      new ol.Coordinate(-77.93255, 37.9555), 'EPSG:4326', 'EPSG:3857'),
  layers: layers,
  renderer: ol.RendererHint.WEBGL,
  zoom: 5
});

var domMap = new ol.Map(document.getElementById('domMap'), {
  renderer: ol.RendererHint.DOM
});
domMap.bindTo('center', webglMap);
domMap.bindTo('layers', webglMap);
domMap.bindTo('resolution', webglMap);
domMap.bindTo('rotation', webglMap);

var attributionControl = new ol.control.Attribution(webglMap);
document.getElementById('attribution').appendChild(
    attributionControl.getElement());

Remove unnecessary precision