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

lib/html/templates/html/impl/impl_CanvasRenderingContext2D.darttemplate

-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
-$!MEMBERS
-
-  void setFillColorRgb(int r, int g, int b, [double a = 1]) {
-    this.fillStyle = 'rgba($r, $g, $b, $a)';
-  }
-
-  void setFillColorHsl(int h, double s, double l, [double a = 1]) {
-    this.fillStyle = 'hsla($h, $s%, $l%, $a)';
-  }
-
-  void setStrokeColorRgb(int r, int g, int b, [double a = 1]) {
-    this.strokeStyle = 'rgba($r, $g, $b, $a)';
-  }
-
-  void setStrokeColorHsl(int h, double s, double l, [double a = 1]) {
-    this.strokeStyle = 'hsla($h, $s%, $l%, $a)';
-  }
-}