Revert 159854 "Promote platform exclusion rules to config.gyp."

> Promote platform exclusion rules to config.gyp.
> 
> BUG=None
> TEST=blink_platform_unittests
> R=abarth@chromium.org
> 
> Review URL: https://codereview.chromium.org/27623002

TBR=tfarina@chromium.org

Review URL: https://codereview.chromium.org/27278005

git-svn-id: svn://svn.chromium.org/blink/trunk@159901 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Fix three bugs in the equals() implementations for css gradients.

1. Linear gradients were considered equal if the first gradient has no x and y
   position and the second has no x but does have y.
2. Same as 1, for radial gradients. (This doesn't happen in practice as
   CSSParser::parseRadialGradient rejects such input, so no test for this case.)
3. Radial gradients without x and y position weren't considered equal even if
   they were.

Found by clang's -Wunused-value in combination with
https://codereview.chromium.org/26205004/

BUG=none
R=eae@chromium.org

Review URL: https://codereview.chromium.org/26147006

git-svn-id: svn://svn.chromium.org/blink/trunk@159903 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Make IndexedDB GC-aware tests use observeGC instead of numberOfLiveNodes

Internals.numberOfLiveNodes can be flaky due to the existence of Nodes
from previous tests run in the same renderer, while Internals.observeGC
is targeted at exactly the object the test is interested in. In addition,
the use of numberOfLiveNodes was already a hack in these tests since they
had to create nodes just for the purpose of observing their destruction.

R=jsbell@chromium.org

Review URL: https://codereview.chromium.org/27745002

git-svn-id: svn://svn.chromium.org/blink/trunk@159904 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove introspection on GC behavior from SVG tearoff regression test

This test is really just a "test passes if it does not crash" test showing
that tearoffs can still be accessed after their elements are dead. There's
no need to use internals.numberOfLiveNodes (which is flaky due to the fact
that we run multiple tests in the same renderer) in this test.

R=pdr@chromium.org

Review URL: https://codereview.chromium.org/27741003

git-svn-id: svn://svn.chromium.org/blink/trunk@159905 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove Mac cursor images that have moved to Chromium

These resources were migrated to the Chromium repo in
https://src.chromium.org/viewvc/chrome?view=rev&revision=228047

R=abarth@chromium.org
BUG=303964

Review URL: https://codereview.chromium.org/27767002

git-svn-id: svn://svn.chromium.org/blink/trunk@159906 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Re-land "Make CompositingState Explicit"

The most recent version of this patch landed in 159118, but was
speculatively reverted in 159473. Now we know this patch was not
at fault, so it can land again.

BUG=261605, 306096
TBR=vollick@chromium.org, jchaffraix@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/26156006

git-svn-id: svn://svn.chromium.org/blink/trunk@159907 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Vector stores Predicate object as OwnPtr instead of raw pointer in XPath.

Vector can handle OwnPtr, so we don't have to delete an element in Vector
manually.

BUG=307055

Review URL: https://codereview.chromium.org/26709019

git-svn-id: svn://svn.chromium.org/blink/trunk@159908 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Count beforeload separately for isolated worlds

BUG=308218

Review URL: https://codereview.chromium.org/26828003

git-svn-id: svn://svn.chromium.org/blink/trunk@159909 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[CSS Shapes] Improve the performance of image valued shapes with large shape-margins

The typical cost of computing the shape-margin boundary of an image-valued shape-outside is now proportional to (2 * shape-margin + image.height) rather than (2 * shape-margin * image.height). The performance improvement comes from skipping sequences of rounded-rectangle intervals that will not contribute to the final result. Each non-empty row in the original image contributes one rounded-rectangle whose corner radius is shape-margin, height is 2 * shape-margin, and width is 2 * shape-margin plus the width of the limits of the intervals on the row.

Renamed private method RasterShape::getIntervals() to intervalsAt() per feedback from an earlier review.

BUG=306270

Review URL: https://codereview.chromium.org/26887009

git-svn-id: svn://svn.chromium.org/blink/trunk@159910 bbb929c8-8fbe-4397-9dbb-9b2b20218538