Replacing non-portable CanvasRenderingContext.setFillColor with more portable variants.

tests/html/canvas_using_html_test.dart

 #library('CanvasUsingHtmlTest');
 #import('../../pkg/unittest/unittest.dart');
 #import('../../pkg/unittest/html_config.dart');
 #import('dart:html', prefix: 'html');
 #import('dart:html');
 
 // Version of Canvas test that implicitly uses dart:html library via unittests.
 
 main() {
   CanvasElement canvas;
   CanvasRenderingContext2D context;
 
   canvas = new Element.tag('canvas');
   canvas.attributes['width'] = 100;
   canvas.attributes['height'] = 100;
   document.body.nodes.add(canvas);
   context = canvas.getContext('2d');
 
   useHtmlConfiguration();
   test('FillStyle', () {
     context.fillStyle = "red";
     context.fillRect(10, 10, 20, 20);
 
     // TODO(vsm): Verify the result once we have the ability to read pixels.
   });
-  test('SetFillColor', () {
-    // With floats.
-    context.setFillColor(10, 10, 10, 10);
-    context.fillRect(10, 10, 20, 20);
-
-    // With rationals.
-    context.setFillColor(10.0, 10.0, 10.0, 10.0);
-    context.fillRect(20, 20, 30, 30);
-
-    // With ints.
-    context.setFillColor(10, 10, 10, 10);
-    context.fillRect(30, 30, 40, 40);
-
-    // TODO(vsm): Verify the result once we have the ability to read pixels.
-  });
   test('StrokeStyle', () {
     context.strokeStyle = "blue";
     context.strokeRect(30, 30, 10, 20);
 
     // TODO(vsm): Verify the result once we have the ability to read pixels.
   });
   test('CreateImageData', () {
     ImageData image = context.createImageData(canvas.width,
                                               canvas.height);
     Uint8ClampedArray bytes = image.data;
 
     // FIXME: uncomment when numeric index getters are supported.
     //var byte = bytes[0];
 
     expect(bytes, hasLength(40000));
   });
 }