Move a boolean flag in RenderInline to RenderObject.

RenderInline has a 1-bit bitfield for a boolean flag, which takes 4 or 8 bytes
of space for each object. The number of RenderInline objects created in a
browsing session can be fairly large, so the extra space allocated for
RenderInline objects might be pretty wasteful.

This patch moves the flag into RenderObject, which still has some unused slots
in its bitfield area. It should cut the extra space in RenderInline.

The similar approach is already attempted for RenderBlocks; there are a couple
of RenderBlock-specific flags defined in RenderObject already. The patch adds
a compile-time assertion, which is similar to the one in RenderBlock, in order
to prevent future regressions.

The patch also makes some clean-ups of the flags defined in RenderObject-
BitFields. Most notably, the comment about the size of RenderObjectBitFields
was wrong :-/

No behavior change, hence no new tests.

BUG=none

Review URL: https://codereview.chromium.org/431923002

git-svn-id: svn://svn.chromium.org/blink/trunk@179690 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Implement ReadableStream::cancel

BUG=393911
R=tyoshino

Review URL: https://codereview.chromium.org/441273003

git-svn-id: svn://svn.chromium.org/blink/trunk@179691 bbb929c8-8fbe-4397-9dbb-9b2b20218538