Remove unused methods in platform/FileSystem

Will do the same cleanup in chrome side as well.

BUG=none (remotely for 257852)
TEST=compile

Review URL: https://chromiumcodereview.appspot.com/21471003

git-svn-id: svn://svn.chromium.org/blink/trunk@155335 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove focus if supportsFocus state is changed.

Changes of *[tabindex], a[href], button[disabled], etc. affect focusable state,
but these changes don't always trigger layout. We need to ask focus check
explicitly.

BUG=265832

Review URL: https://chromiumcodereview.appspot.com/21055009

git-svn-id: svn://svn.chromium.org/blink/trunk@155336 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Row spanning cell content is flowing out of the cell border if this row spanning cell comes under the boundries of other row spanning cell.

Inner row spanning cell height was not considered in table layout So Height
of the row spanning cell was not proper. Overlapping row spanning cells was
not handles.

Inner row spanning cell should handle first in the table. So we are rearranging
the list of row spanning cells so that inner row spanning cell will handled first
for spredding remaining logical height in the rows than outer row spanning cell.

List of row spanning cells is already sorted in ascending order by their
rowIndexs.
We are rearranging the row spanning cell's list and pushing inner cell before
its outer cell. Also if 2 or more row spanning cells are same but their heights
are different then pushing height-est row spanning cell before the lower height row
spanning cells.
After rearranging them, we apply the process of spreading remaining logical
height into rows.

R=jchaffraix@chromium.org
BUG=252120

Review URL: https://chromiumcodereview.appspot.com/19635004

git-svn-id: svn://svn.chromium.org/blink/trunk@155337 bbb929c8-8fbe-4397-9dbb-9b2b20218538