Fix empty image drawing (#1605)

Empty raster (for example coming from path with empty bound
rasterization, ...) drawing threw error.
This change prevent raster drawing in that case.
Closes #1320

CHANGELOG.md

@@ -1,5 +1,13 @@
 # Change Log
 
+## Prebuilt version
+
+### Fixed
+
+- Fix empty image drawing (#1320).
+
+### Added
+
 ## `0.11.8`
 
 ### News

src/item/Raster.js

@@ -753,7 +753,8 @@ var Raster = Item.extend(/** @lends Raster# */{
 
     _draw: function(ctx, param, viewMatrix) {
         var element = this.getElement();
-        if (element) {
+        // Only draw if image is not empty (#1320).
+        if (element && element.width > 0 && element.height > 0) {
             // Handle opacity for Rasters separately from the rest, since
             // Rasters never draw a stroke. See Item#draw().
             ctx.globalAlpha = this._opacity;

test/tests/Item.js

@@ -945,3 +945,9 @@ test('Children global matrices are cleared after parent transformation', functio
     group.translate(100, 0);
     equals(item.localToGlobal(item.getPointAt(0)), new Point(100, 100));
 });
+
+test('Item#rasterize() with empty bounds', function() {
+    new Path.Line([0, 0], [100, 0]).rasterize();
+    view.update();
+    expect(0);
+});