Attach (recommended) or Link to PDF file here:
[page226-simple.pdf](https://github.com/mozilla/pdf.js/files/2309555/page226-simple.pdf)

Configuration:
- Web browser and its version: Firefox Quantum 61.0.2 (64-bit) and Chrome 68.0.3440.106
- Operating system and its version: Windows 8.1
- PDF.js version: latest version from http://mozilla.github.io/pdf.js/build/pdf.js
- Is a browser extension: No

Steps to reproduce the problem:
1. Copy this html in the same folder as the pdf and open it in a browser.

```
<!doctype html>
<html>
<head>
	<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
	<script src="http://mozilla.github.io/pdf.js/build/pdf.js"></script>
	<script>
		function pdfToPlainText(pdfData) {
			pdfjsLib.disableWorker = true;
			var pdf = pdfjsLib.getDocument(pdfData);
			pdf.then(getPages);
		}
		function getPages(pdf) {
			var pagePromiseArr = [];
			for (var i = 0; i < pdf.numPages; i++) {
				pagePromiseArr.push(pdf.getPage(i + 1));
			}
			Promise.all(pagePromiseArr).then(getPagesText);
		}
		function getPagesText(pageArr) {
			var textContentPromiseArr = [];
			for(var j=0; j<pageArr.length; j++)
			{
				var page = pageArr[j];
				textContentPromiseArr.push(page.getTextContent());
				
			}
			Promise.all(textContentPromiseArr).then(function(textContentArr) {
				
				for(var j=0; j<textContentArr.length; j++)
				{
					var textContent = textContentArr[j];
					textContent.items.forEach(function(o) {
						$("#pdf").append(o.str);
						$("#pdf").append("<br>");
					});	

				}
			});
		}
	</script>
</head>
<body onload="pdfToPlainText('page226-simple.pdf')">
	<div id="pdf" style='font-family: "Courier New", monospace; font-size: 10px'></div>
</body>
</html>
```

What is the expected behavior?

The text should be (this is the text that you can copy and paste from Acrobat Reader or Chrome's PDF viewer):

```
Vehicles Involved and Human Injuries
fields should be left blank by default until
operator inputs an accurate value.
```

What went wrong?

The text has extra spaces inside most of the words:

```
Vehi cl es Invol ved and Human Inj uri es
fi el ds s houl d be l eft bl ank by defaul t unti l
operator i nputs an accurate val ue. 
```

The same bug happens in Firefox default PDF viewer (which uses pdf.js):
* If you open the file in Firefox
* select all, 
* copy 
* and paste the text in Notepad for example.
const fontHeight = Math.hypot(tx[2], tx[3]);
  const fontAscent = fontHeight * getAscent(style.fontFamily, ctx);
  let left, top;
  if (angle === 0) {
    left = tx[4];
    top = tx[5] - fontAscent;
  } else {
    left = tx[4] + fontAscent * Math.sin(angle);
    top = tx[5] - fontAscent * Math.cos(angle);
  }
  
  
  textDiv.style.left = `${left}px`;
  textDiv.style.top = `${top}px`;
  textDiv.style.fontSize = `${fontHeight}px`;
  textDiv.style.fontFamily = style.fontFamily;
  
  textDiv.setAttribute("role", "presentation");
  textDiv.textContent = geom.str;
  
  textDiv.dir = geom.dir;
  
  
  if (task._fontInspectorEnabled) {
    textDiv.dataset.fontName = geom.fontName;
  }
  if (angle !== 0) {
    textDivProperties.angle = angle * (180 / Math.PI);
  }