Cherry-pick: Add a legacy quirk for 'user-scalable=no' case

Cherry-pick of Blink http://crrev.com/53053002

To reduce amount of changes, we are not adding a new quirk
setting here as in the upstream patch, instead we are reusing
supportTargetDensityDPI for legacy behavior.

Bug: 11337642

Original description:

[Android WebView] Add a legacy quirk for 'user-scalable=no' case

In legacy Android WebView implementation, having 'user-scalable=no'
in the viewport meta tag ignores scale set via 'initial-scale' and
also affects wide viewport quirk behavior.

BUG=312691

Change-Id: I8731a76781d46622fd3fb61fbdb4342db028fcd9
1 file changed