Backport PR elastic#8372

---------

**Commit 1:**
adding mapLoaded event to tile_map visualization

* Original sha: 0f673d7c14ee9fa638b7f284f5254ef570f17c93 [formerly e198f41]
* Authored by ppisljar <[email protected]> on 2016-09-20T10:22:43Z

**Commit 2:**
adding rendered event to each chart and renderComplete to vis

* Original sha: 39530305081240930e33369de64db51fd68e7fc5 [formerly 8324f5a]
* Authored by ppisljar <[email protected]> on 2016-09-20T17:54:52Z

**Commit 3:**
fixing based on Spencers comments

* Original sha: fabc53d93bde22909ee696a5d18ce21434e0d638 [formerly b4780fe]
* Authored by ppisljar <[email protected]> on 2016-09-22T07:24:19Z


Former-commit-id: c064f87

src/ui/public/vislib/lib/handler/handler.js

@@ -116,14 +116,23 @@ export default function HandlerBaseClass(Private) {
       });
 
       // render the chart(s)
-      selection.selectAll('.chart')
-      .each(function (chartData) {
+      let loadedCount = 0;
+      const chartSelection = selection.selectAll('.chart');
+      chartSelection.each(function (chartData) {
         const chart = new self.ChartClass(self, this, chartData);
 
         self.vis.activeEvents().forEach(function (event) {
           self.enable(event, chart);
         });
 
+        chart.events.on('rendered', () => {
+          loadedCount++;
+          if (loadedCount === chartSelection.length) {
+            // events from all charts are propagated to vis, we only need to fire renderComplete on one (first)
+            charts[0].events.emit('renderComplete');
+          }
+        });
+
         charts.push(chart);
         chart.render();
       });

src/ui/public/vislib/visualizations/_map.js

@@ -211,6 +211,17 @@ export default function MapFactory(Private, tilemap, $sanitize) {
 
       this._tileLayer.on('tileload', saturateTiles);
 
+      this._tileLayer.on('load', () => {
+        if (!self._events) return;
+
+        self._events.emit('rendered', {
+          chart: self._chartData,
+          map: self.map,
+          center: self._mapCenter,
+          zoom: self._mapZoom,
+        });
+      });
+
       this.map.on('unload', function () {
         self._tileLayer.off('tileload', saturateTiles);
       });

src/ui/public/vislib/visualizations/area_chart.js

@@ -365,6 +365,10 @@ export default function AreaChartFactory(Private) {
             timeMarker.render(svg);
           }
 
+          self.events.emit('rendered', {
+            chart: data
+          });
+
           return svg;
         });
       };

src/ui/public/vislib/visualizations/column_chart.js

@@ -315,6 +315,10 @@ export default function ColumnChartFactory(Private) {
             timeMarker.render(svg);
           }
 
+          self.events.emit('rendered', {
+            chart: data
+          });
+
           return svg;
         });
       };

src/ui/public/vislib/visualizations/line_chart.js

@@ -339,6 +339,10 @@ export default function LineChartFactory(Private) {
             timeMarker.render(svg);
           }
 
+          self.events.emit('rendered', {
+            chart: data
+          });
+
           return svg;
         });
       };

src/ui/public/vislib/visualizations/pie_chart.js

@@ -202,6 +202,10 @@ export default function PieChartFactory(Private) {
           const path = self.addPath(width, height, svg, slices);
           self.addPathEvents(path);
 
+          self.events.emit('rendered', {
+            chart: data
+          });
+
           return svg;
         });
       };