[CSS Grid Layout] Handle percentages of indefinite sizes in minmax()

After r164062 percentages of indefinite sizes were correctly
computed to "auto". The problem is that we were not doing it when
the percentage was inside the minmax() function. In those cases
it should compute to min-content for the min track sizing
function or to max-content for the max track sizing function.

Added a couple of tests, one to verify that we do not assert with
percentages inside minmax() and another one to verify that we
properly compute the percentage of indefinite size in various
situations.

BUG=401477,409085

Review URL: https://codereview.chromium.org/450093004

git-svn-id: svn://svn.chromium.org/blink/trunk@181800 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Removed stray declared method.

Left-over from the removal of diffNeedsRecompositeLayer [1].

[1] https://codereview.chromium.org/360103008

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/565583002

git-svn-id: svn://svn.chromium.org/blink/trunk@181801 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[XHR] Accept data on didReceiveData call even if responseType is set to Blob

Since Blink 175446
https://src.chromium.org/viewvc/blink?revision=175446&view=revision
we're loading data into a file. The downloadToFile flag is determined in
createRequest() i.e. inside xhr.send() call. But responseType is allowed
to be changed even after xhr.send() call.

Accumulate data into m_binaryResponseBuilder and create a Blob from it
anyway if m_downloadingToFile is not set.

BUG=412704

Review URL: https://codereview.chromium.org/562563003

git-svn-id: svn://svn.chromium.org/blink/trunk@181802 bbb929c8-8fbe-4397-9dbb-9b2b20218538