Use the outermost float for shape-outside

Shape outside was using the last float encountered on the line, assuming it
would always be the outermost float. However, this is not necessarily true, so
switch to using the outermost float. This has the advantage of also only
needing one saved float when computing the offset, not two.

BUG=271774

Review URL: https://chromiumcodereview.appspot.com/23084002

git-svn-id: svn://svn.chromium.org/blink/trunk@156038 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: handle gesture tap event while in inspecting element mode.

BUG=272109
TBR=vsevik

Review URL: https://chromiumcodereview.appspot.com/23085004

git-svn-id: svn://svn.chromium.org/blink/trunk@156039 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Update window.devicePixelRatio on browser zoom

Update window.devicePixelRatio on full page zoom so that it
accurately portraitists the ratio between css and device pixels.

This matches the behavior of Firefox and the IE 11 preview.

BUG=177836
R=eseidel@chromium.org, dglazkov@chromium.org
TEST=fast/dom/Window/device-pixel-ratio-on-zoom.html

Review URL: https://chromiumcodereview.appspot.com/23000005

git-svn-id: svn://svn.chromium.org/blink/trunk@156040 bbb929c8-8fbe-4397-9dbb-9b2b20218538