Modifying shouldScaleColumns for proper scaling of nested table columns

Modifying shouldScaleColumns for proper scaling of nested table columns.

For scenarios where the containing table width is of percent or fixed type, but with width specified as either 0px or 0%, scaling of the nested or inner table columns is still allowed. Also, if the containing table was floated or positioned, we would still allow scaling of the nested table's columns.
We should consider a specified width value of either 0px or 0%, similar in behavior to an auto width and disallow the scaling of nested columns for that case.
Similarly, if the containing table is either floated or positioned, we should again disallow the scaling of its nested table's columns.

R=jchaffraix@chromium.org
BUG=244182

[Julien - ping for review, 2013-05-29 20:56:14]

Sorry for the delay, catching up on reviews after gardening.

https://codereview.chromium.org/15650011/diff/1/Source/core/rendering/AutoTab...
File Source/core/rendering/AutoTableLayout.cpp (right):

https://codereview.chromium.org/15650011/diff/1/Source/core/rendering/AutoTab...
Source/core/rendering/AutoTableLayout.cpp:203: ||
cell->table()->isFloatingOrOutOfFlowPositioned())
How about some testing for these cases?

[eae, 2015-07-14 22:39:59]

Ping? What's the status on this, ideally we'd like to fix this issue...