Scale to legibleScale if double tap would barely zoom in from zoomed out state.

The motivation for this is for double tap to zoom in when viewing an image, (no html) which we believe to be more user friendly than just silently doing nothing.
It could potentially be a slight change in behaviour in other cases as well (text spanning all the way from left edge to right edge) though we haven't noticed any problems like this in practice.

BUG=280133

Review URL: https://chromiumcodereview.appspot.com/23461009

git-svn-id: svn://svn.chromium.org/blink/trunk@156966 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Make layout test editing/selection/select-start-remove-root-crash.html stable

This patch makes layout test editing/selection/select-start-remove-root-crash.html stable by using load event to kick selection change rather then interval timer. It seems flakyness is caused by heavy load bot that execute "SelectAll" command before rendering contents where nothing to select.

BUG=282090
TEST=LayoutTests/editing/selection/select-start-remove-root-crash.html
R=tkent@chromium.org

Review URL: https://codereview.chromium.org/23685003

git-svn-id: svn://svn.chromium.org/blink/trunk@156967 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Introduce toSVGFEDiffuseLightingElement(), and use it

As a step to clean-up static_cast<SVGXXX>, toSVGFEDiffuseLightingElement() is added to clean-up
static_cast<SVGFEDiffuseLightingElement*>.

BUG=N/A

Review URL: https://chromiumcodereview.appspot.com/23529005

git-svn-id: svn://svn.chromium.org/blink/trunk@156968 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[Android WebView] Avoid expanding layout width to match the old WebView

The old WebView doesn't expand the layout width for the resolved initial scale.

BUG=277369

Review URL: https://chromiumcodereview.appspot.com/23038013

git-svn-id: svn://svn.chromium.org/blink/trunk@156969 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Text zoom level should not affect page zoom level.

The text-only zoom level should not affect the return value of
WebView::zoomLevel().

BUG=275749

Review URL: https://chromiumcodereview.appspot.com/23147003

git-svn-id: svn://svn.chromium.org/blink/trunk@156971 bbb929c8-8fbe-4397-9dbb-9b2b20218538