Oilpan: fix build after r180084.

Oilpan: fix build after r180084.

Address type conversion subtlety over RawPtr<>s. We have at hand:

 Handle<Value> toV8(PassRefPtrWillBeRawPtr<NodeList>, ...);

 template<NodeType>class StaticNodeTypeList : public NodeList {
   public:
       static PassRefPtrWillBeRawPtr<StaticNodeTypeList> adopt(..);
       ...
   }

 typedef StaticNodeTypeList<Element> StaticElementList;

and the call

 toV8(StaticElementList::adopt(namedItems), ....);

For the toV8() call to be successfully resolved, the adopt() result
must be convertible to PassRefPtrWillBeRawPtr<NodeList>. For the non-Oilpan
case, we do have the

   PassRefPtr(const PassRefPtr<U>, EnsurePtrConvertibleArgDecl(U, T))

constructor at hand, which will convert the PassRefPtr<StaticElementList>
into PassRefPtr<NodeList>. We do not have the corresponding type-convertible
constructor over RawPtr<>, as providing that runs into problems when
using RawPtr<> as part of the PassOwnPtrWillBeRawPtr transition type.

Address/step-around-the-issue by being explicit about the conversion.

TBR=haraken,oilpan-reviews
BUG=
NOTRY=true

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=180096

[sof, 2014-08-12 19:36:15]

Please take a look.

[sof, 2014-08-12 19:36:28]

The CQ bit was checked by sigbjornf@opera.com

[commit-bot: I haz the power, 2014-08-12 19:37:36]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/sigbjornf@opera.com/451303003/1

[commit-bot: I haz the power, 2014-08-12 19:38:26]

Change committed as 180096

[sof, 2014-08-12 20:48:23]

I misdiagnosed the reason why the explicit conversion is  needed -- there really
is an ambiguity for RawPtr<T> due to it having a T* type conversion operator, so
there is no way around being explicit. It has nothing to do with
RawPtr<T>::RawPtr(const RawPtr<U>), as previously stated.

Will tidy up the FIXME tomorrow, with a clear(er) head.

[haraken, 2014-08-12 23:29:06]

rubberstamp LGTM