ParentNode#appendChild(null) shouldn't crash

ParentNode#appendChild(null) shouldn't crash

We just needed to throw the proper exception when handed null for a
non-nullable argument.

R=esprehn@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/74759efd00b2933e15448c25e44472c6f730aae9

[esprehn, 2015-02-17 18:06:52]

esprehn@chromium.org changed reviewers:
+ esprehn@chromium.org

[esprehn, 2015-02-17 18:06:53]

lgtm

https://codereview.chromium.org/934863002/diff/20001/sky/engine/tonic/dart_ex...
File sky/engine/tonic/dart_exception_factory.cc (right):

https://codereview.chromium.org/934863002/diff/20001/sky/engine/tonic/dart_ex...
sky/engine/tonic/dart_exception_factory.cc:30: Dart_Handle empty_string =
Dart_NewStringFromCString("");
Do we want a shared per isolate empty string? Exceptions are probably rare, so
this is fine I suppose.

[abarth-chromium, 2015-02-17 18:14:05]

https://codereview.chromium.org/934863002/diff/20001/sky/engine/tonic/dart_ex...
File sky/engine/tonic/dart_exception_factory.cc (right):

https://codereview.chromium.org/934863002/diff/20001/sky/engine/tonic/dart_ex...
sky/engine/tonic/dart_exception_factory.cc:30: Dart_Handle empty_string =
Dart_NewStringFromCString("");
On 2015/02/17 at 18:06:53, esprehn wrote:
> Do we want a shared per isolate empty string? Exceptions are probably rare, so
this is fine I suppose.

It looks like Dart_NewStringFromCString("") is relatively expensive (e.g., it
really does allocate storage in the heap).  It would be pretty easy to add an
entry for the empty string to the DartStringCache, but I'm not sure its worth
doing for this use case.  Let's do it if the topic comes up again.

[abarth-chromium, 2015-02-17 18:15:31]

Committed patchset #2 (id:20001) manually as
74759efd00b2933e15448c25e44472c6f730aae9 (presubmit successful).

[abarth-chromium, 2015-02-17 18:29:52]

Filed https://code.google.com/p/dart/issues/detail?id=22457 to see if we want to
add this cache inside the DartVM