Downstream bug in Puppeteer: https://github.com/GoogleChrome/puppeteer/issues/733

Protocol command Page.captureScreenshot rounds clipping area to even numbers.

Puppeteer repro on Mac OS X:


```js
const puppeteer = require('puppeteer');
(async() => {
  const browser = await puppeteer.launch()
  const page = await browser.newPage()
  await page.screenshot({
    clip: {
      x: 0,
      y: 0,
      width: 11,
      height: 11
    },
    path: 'clip.png'
  });
  await page.close();
  browser.close();
})();
```

Expected: clip.png to be 11x11
Actual: clip.png is 12x12
 

Downstream bug in Puppeteer: https://github.com/GoogleChrome/puppeteer/issues/733

Protocol command Page.captureScreenshot rounds clipping area to even numbers.

Puppeteer repro on Mac OS X:


const puppeteer = require('puppeteer');
(async() => {
  const browser = await puppeteer.launch()
  const page = await browser.newPage()
  await page.screenshot({
    clip: {
      x: 0,
      y: 0,
      width: 11,
      height: 11
    },
    path: 'clip.png'
  });
  await page.close();
  browser.close();
})();



Expected: clip.png to be 11x11
Actual: clip.png is 12x12