Replace static_cast<HTMLElememt*> with toHTMLElement

This replaces everyone who was casting to HTMLElement* manually and
simplifies some code.

R=abarth@chromium.org

Review URL: https://chromiumcodereview.appspot.com/17522002

git-svn-id: svn://svn.chromium.org/blink/trunk@152843 bbb929c8-8fbe-4397-9dbb-9b2b20218538
stop looking for DRT binary to determine the architecture

We no longer build DumpRenderTree, but the check to determine whether to
run 32-bit or 64-bit linux wasn't updated to look at content_shell instead.

This is a temporary fix to get the builder working again. I'll file a bug
to fix this properly and clean up all the lingering content_shell/drt
flags.

TBR=jochen@chromium.org, steveblock@chromium.org
BUG=252558

Review URL: https://codereview.chromium.org/17351018

git-svn-id: svn://svn.chromium.org/blink/trunk@152844 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Clear button for date/time inputs should be zoomable on Mac

We will stop using NSCancelButtonCell and draw it using GraphicsContext.
This will also enable zooming for search field cancel buttons.

The change to RenderThemeChromiumMac::controlSizeForSystemFont fixes a bug where all controls were drawn with NSRegularControlSize when zoomed. Because we fixed this we had to introduce different padding depending on the control size (searchFieldHorizontalPaddings).

BUG=247572

Review URL: https://chromiumcodereview.appspot.com/16532002

git-svn-id: svn://svn.chromium.org/blink/trunk@152845 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove unneeded static_casts from SelectorChecker

SelectorChecker::checkOne casts to StyledElement just to call classNames, but
this method is on Element so there's no reason for this. The cast here also
looks pretty suspect. The method also casts to HTMLFrameElementBase to call
containsFullScreenElement which is also on Element so the cast can be removed.

Review URL: https://chromiumcodereview.appspot.com/17525002

git-svn-id: svn://svn.chromium.org/blink/trunk@152846 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Revert "Add failing expectations for a number of  canvas, SVG and webaudio tests on Linux"

This reverts commit 9389d8129bd13f1c0024835aa2d14718b866cd44.

A temporary fix for the underlying issue has been made in
https://src.chromium.org/viewvc/chrome?view=rev&revision=152844

See bug for details.

BUG=252052
TBR=

Review URL: https://codereview.chromium.org/17073004

git-svn-id: svn://svn.chromium.org/blink/trunk@152847 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove many static_casts to Element types from AccessibilityNodeObject

Some of these casts were to overly specific types, like casting to HTMLFrameElementBase*
just to call getAttribute. In other cases we can cast to a more generic type like
HTMLTextFormControlElement to avoid the extra cases the code originally had.

Review URL: https://chromiumcodereview.appspot.com/17524002

git-svn-id: svn://svn.chromium.org/blink/trunk@152848 bbb929c8-8fbe-4397-9dbb-9b2b20218538