[Android WebView] Prepare to remove AwSettings.LayoutAlgorithm

Usages of AwSettings.LayoutAlgorithm need to be replaced with
WebSettings.LayoutAlgorithm.

This change also fixes a couple of trivial presubmit warnings in
existing code.

BUG=332089

Review URL: https://codereview.chromium.org/115253004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243576 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 243576
Rename RootWindowHost to WindowTreeHost

TBR=sky@chromium.org
http://crbug.com/308843

Review URL: https://codereview.chromium.org/126513004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243578 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 243578