title: something wrong to the edge of my custom view when calling canvas.drawArc()
body: <p>I suppose to draw a circle view,and I set my paint like this:</p>
  
  <pre><code>    mPaintForeground.setColor(mColorForeground);
      mPaintForeground.setStyle(Paint.Style.STROKE);
      mPaintForeground.setStrokeCap(Paint.Cap.ROUND);
      mPaintForeground.setStrokeWidth(20);
      mPaintForeground.setAntiAlias(true);
  </code></pre>
  
  <p>and draw it:</p>
  
  <pre><code>   mBitmap = Bitmap.createBitmap((int) mRect.width(), (int) mRect.height(),
              Bitmap.Config.ARGB_8888);
     Canvas canvas = new Canvas(mBitmap);
     if (!loadingFinished) {
         canvas.drawArc(mRect, -90, mProgress, false, mPaintForeground);
     }
  </code></pre>
  
  <p>But I found some the edge of view has been cut.<br>
  <img src="https://i.stack.imgur.com/qglAL.jpg" alt="edge of arc"><br>
  So how can I control the radius length in the arc?Is the problem in mRect?</p>