fix text context and complete gradient js code

elements/LinearGradient.js

@@ -11,26 +11,7 @@ import {LINEAR_GRADIENT} from '../lib/extract/extractBrush';
 import insertColorStopsIntoArray from '../lib/insertProcessor';
 
 function LinearGradientGenerator(stops, x1, y1, x2, y2) {
-    var type = LINEAR_GRADIENT;
-
-    if (arguments.length < 5) {
-        var angle = ((x1 == null) ? 270 : x1) * Math.PI / 180;
-
-        var x = Math.cos(angle);
-        var y = -Math.sin(angle);
-        var l = (Math.abs(x) + Math.abs(y)) / 2;
-
-        x *= l; y *= l;
-
-        x1 = 0.5 - x;
-        x2 = 0.5 + x;
-        y1 = 0.5 - y;
-        y2 = 0.5 + y;
-        this._bb = true;
-    } else {
-        this._bb = false;
-    }
-    var brushData = [type, +x1, +y1, +x2, +y2];
+    var brushData = [LINEAR_GRADIENT, x1, y1, x2, y2];
     insertColorStopsIntoArray(stops, brushData, 5);
     this._brush = brushData;
 }
@@ -53,20 +34,9 @@ class LinearGradient extends Gradient{
             x2,
             y2
         } = this.props;
-        let gradientProps = [x1, y1, x2, y2];
         return super.render(
-            gradientProps,
-            function (factories, stops, boundingBox, opacity) {
-                return new LinearGradientGenerator(
-                    stopsOpacity(stops, opacity),
-                    factories[0](boundingBox.width),
-                    factories[1](boundingBox.height),
-                    factories[2](boundingBox.width),
-                    factories[3](boundingBox.height)
-                );
-            },
-            function (stops, opacity) {
-                return new LinearGradientGenerator(stopsOpacity(stops, opacity), ...gradientProps);
+            (stops, opacity) => {
+                return new LinearGradientGenerator(stopsOpacity(stops, opacity), ...[x1, y1, x2, y2]);
             }
         );
     }