[CSS Shapes] StyleResolver::loadPendingShapeImage() should check its ShapeValue parameter more carefully

In https://chromiumcodereview.appspot.com/17092005 I incorrectly refactored the StyleResolver::loadPendingImages() cases for CSSPropertyWebkitShapeInside and CSSPropertyWebkitShapeOutside. The new StyleResolver::loadPendingShapeImage() method check that its argument is non-null and that the argument's image is a pending image.

I've restored the missing checks.

I also changed the way loadPendingShapeImage() specifies its ResourceLoaderOptions as Adam suggested in the review of the original change:
https://codereview.chromium.org/17092005/diff/8001/Source/core/css/resolver/StyleResolver.cpp#newcode3575

BUG=253057

Review URL: https://chromiumcodereview.appspot.com/17321013

git-svn-id: svn://svn.chromium.org/blink/trunk@153014 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove no-op GroupSettings object from PageGroup and Worker code

The GroupSettings object appears to have been used on non-Chromium
WebKit ports to pass information from the Page to the LocalStorage
and IndexedDB. But in Blink/Chromium, that information is never used;
the browser side impls of the storage APIs provide that info instead.

Besides ripping out GroupSettings, this removes unused the unused quota
plumbing for SessionStorage as well.

R=abarth

Review URL: https://chromiumcodereview.appspot.com/17583016

git-svn-id: svn://svn.chromium.org/blink/trunk@153015 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove lines that now pass according to flakiness dashboard

I had some problem with garden-o-matic... this should fix the last
issue. See also https://codereview.chromium.org/17624005

TBR=ojan@chromium.org
BUG=

Review URL: https://codereview.chromium.org/17721002

git-svn-id: svn://svn.chromium.org/blink/trunk@153016 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove detect-mismatched-virtual-const.

Clang has a warning for this, so there's no need for this script.

BUG=none

Review URL: https://chromiumcodereview.appspot.com/17694003

git-svn-id: svn://svn.chromium.org/blink/trunk@153017 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Removed runtime check for canvas blend modes

BUG=252439

Review URL: https://chromiumcodereview.appspot.com/17569019

git-svn-id: svn://svn.chromium.org/blink/trunk@153018 bbb929c8-8fbe-4397-9dbb-9b2b20218538