Use shrink-to-fit for width for Button, input, select, textarea, and legend treat width value of 'auto' as 'intrinsic'.

Per CSS 2.1 section 10.3.8, the width should be the width an input would normally have (rule 1 in 10.3.8), and the 'right' value should be ignored because the values are over-constrained (rule 6 in 10.3.8).

BUG=281380

Review URL: https://codereview.chromium.org/24360004

git-svn-id: svn://svn.chromium.org/blink/trunk@159860 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Implement new Blink IDL attribute [SetReference]

SetReference is a new Blink IDL attribute which can be used to specify dependency from a wrapper to another. This is implemented by calling v8::Isolate::SetReference on minor GC prologues. This has a lower overhead compared to old technique using SetHiddenValueTo.

BUG=307341

Review URL: https://codereview.chromium.org/26792002

git-svn-id: svn://svn.chromium.org/blink/trunk@159861 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Refactoring of WebKit::WebData

Refactoring of WebKit::WebData:
- using of WebPrivatePtr and hence simplifiction of most of the WebData class methods
- removal of unnecessary 'operator RefPtr<WebCore::SharedBuffer>() const'

Review URL: https://codereview.chromium.org/27103003

git-svn-id: svn://svn.chromium.org/blink/trunk@159862 bbb929c8-8fbe-4397-9dbb-9b2b20218538