Narrow String::CharAt from int32_t to uint16_t.

Narrow String::CharAt from int32_t to uint16_t.

R=asiva@google.com

Committed: https://code.google.com/p/dart/source/detail?r=40178

[rmacnak, 2014-09-11 00:24:40]

rmacnak@google.com changed reviewers:
+ asiva@google.com

[siva, 2014-09-11 01:30:31]

There are couple of issues:
- in dart_api_impl.cc we have some static_cast<uint16_t> which needs to be
removed
- we have some invocations of Smi::New with the return value of CharAt this
needs to be probably explicitly cast.

[rmacnak, 2014-09-11 19:51:33]

On 2014/09/11 01:30:31, siva wrote:
> There are couple of issues:
> - in dart_api_impl.cc we have some static_cast<uint16_t> which needs to be
> removed
> - we have some invocations of Smi::New with the return value of CharAt this
> needs to be probably explicitly cast.

Also updated the string indexing natives.

[siva, 2014-09-11 20:23:00]

lgtm

https://codereview.chromium.org/560113002/diff/60001/runtime/lib/string.cc
File runtime/lib/string.cc (right):

https://codereview.chromium.org/560113002/diff/60001/runtime/lib/string.cc#ne...
runtime/lib/string.cc:245: GET_NON_NULL_NATIVE_ARGUMENT(Integer, index,
arguments->NativeArgAt(1));
Can you add a comment that this function returns a 16 bit UTF-16 code unit at
the specified index.

[rmacnak, 2014-09-11 20:54:57]

On 2014/09/11 20:23:00, siva wrote:
> lgtm
> 
> https://codereview.chromium.org/560113002/diff/60001/runtime/lib/string.cc
> File runtime/lib/string.cc (right):
> 
>
https://codereview.chromium.org/560113002/diff/60001/runtime/lib/string.cc#ne...
> runtime/lib/string.cc:245: GET_NON_NULL_NATIVE_ARGUMENT(Integer, index,
> arguments->NativeArgAt(1));
> Can you add a comment that this function returns a 16 bit UTF-16 code unit at
> the specified index.

Added.

[rmacnak, 2014-09-11 20:55:43]

Committed patchset #5 (id:80001) manually as 40178 (presubmit successful).