IDL clean-up: Rename is_nullable_simple => is_implicit_nullable

IDL clean-up: Rename is_nullable_simple => is_implicit_nullable

... and introduce is_explicit_nullable that is mutually exclusive (for
nullable types.)

It turns out that the only actual use of is_implicit_nullable right now
is in the definition of is_explicit_nullable, but having both is fine,
for symmetry.

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=177912

[Jens Widell, 2014-07-10 15:44:05]

PTAL

It turns out the reason the previous design was wrong was that it was only
is_explicit_nullable (and idl_type.is_nullable) that we were really ever
interested in. I kept is_implicit_nullable around for symmetry (it helps explain
is_explicit_nullable, if nothing else.)

[haraken, 2014-07-10 15:48:16]

LGTM

https://codereview.chromium.org/384773004/diff/1/Source/bindings/scripts/v8_a...
File Source/bindings/scripts/v8_attributes.py (right):

https://codereview.chromium.org/384773004/diff/1/Source/bindings/scripts/v8_a...
Source/bindings/scripts/v8_attributes.py:117: 'is_explicit_nullable':
idl_type.is_explicit_nullable,

alphabetical order

[Jens Widell, 2014-07-10 15:53:18]

https://codereview.chromium.org/384773004/diff/1/Source/bindings/scripts/v8_a...
File Source/bindings/scripts/v8_attributes.py (right):

https://codereview.chromium.org/384773004/diff/1/Source/bindings/scripts/v8_a...
Source/bindings/scripts/v8_attributes.py:117: 'is_explicit_nullable':
idl_type.is_explicit_nullable,
On 2014/07/10 15:48:16, haraken wrote:
> alphabetical order

Argh! We should implement a presubmit check for this. :-)

[Jens Widell, 2014-07-11 06:29:16]

The CQ bit was checked by jl@opera.com

[commit-bot: I haz the power, 2014-07-11 06:29:36]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jl@opera.com/384773004/20001

[commit-bot: I haz the power, 2014-07-11 07:39:46]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  win_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/win_blink_rel/builds/16392)

[commit-bot: I haz the power, 2014-07-11 08:11:50]

Change committed as 177912