title: CAShapeLayer fillcolor arc animation not working
body: <p>I am using below code to draw a Pie slice layer with CAShapeLayer.</p>
  
  <pre><code>CGFloat endAngle = (M_PI*2/5)-M_PI_2;
  
  CAShapeLayer *outerBorderCircle = [CAShapeLayer layer];
  int outerradius = self.frame.size.width/2;
  UIBezierPath *path = [UIBezierPath bezierPath];
  [path moveToPoint:CGPointMake(outerradius, outerradius)];
  [path addLineToPoint:CGPointMake(outerradius, self.outerCircleBorder)];
  [path addArcWithCenter:CGPointMake(outerradius,outerradius) radius:outerradius-self.outerCircleBorder startAngle:-M_PI_2 endAngle:endAngle clockwise:YES];
  [path closePath];
  outerBorderCircle.path = path.CGPath;
  
  outerBorderCircle.fillColor = [UIColor whiteColor].CGColor;
  outerBorderCircle.strokeColor = self.borderShadowColor.CGColor;
  outerBorderCircle.lineWidth = self.outerCircleBorder;
  outerBorderCircle.lineJoin = kCALineJoinRound;
  outerBorderCircle.zPosition = MAXFLOAT;
  
  CABasicAnimation *startanimation = [CABasicAnimation animationWithKeyPath:@"fillColor"];
  startanimation.removedOnCompletion = YES;
  startanimation.fromValue = (id)[[UIColor clearColor] CGColor];
  startanimation.toValue = (id)[[UIColor whiteColor] CGColor];
  startanimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
  startanimation.duration = 10.0;
  [startanimation setFillMode:kCAFillModeBoth];
  
  [outerBorderCircle addAnimation:startanimation forKey:@"fillColor"];
  
  [self.layer addSublayer:outerBorderCircle];
  </code></pre>
  
  <p>But animation part working as fade in fade out. But i need to animate arc kind of animation.</p>
  
  <p>Please help me.</p>