Speed up line parsing for simple line layout (part I)

Speed up line parsing for simple line layout (part I)
https://bugs.webkit.org/show_bug.cgi?id=137275

Reviewed by Antti Koivisto.

Extend simple line layout performance test with a few more cases.
Now we've got:
<div center
<div right
<div justify
<div white-space: pre (new)
<div overflow-wrap: break-word (new)
<pre
<pre white-space: pre-wrap
<pre white-space: pre-line (new)
<pre white-space: nowrap (new)
<pre white-space: pre-wrap overflow-wrap: break-word
<div + embedded <span etc.
<div + br

* Layout/line-layout-simple.html:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@175048 268f45cc-cd09-0410-ab3c-d52691b4dbfc