Use "int" instead of "long" for bindings where the WebIDL uses "long".

ABANDONED!!!

Use "int" instead of "long" for bindings where the WebIDL uses "long".

BUG=267360

[alecflett, 2013-08-02 15:10:14]

lgtm for the indexeddb stuff - though dgrogan@ may want to take a look at the
FIXME - I think we use -1 internally, but I don't know how that relates to the
max 'long' that can come from JS.

[eroman, 2013-08-13 15:38:10]

abarth: ping. Should I break this into separate changelists, or abandon?

[jsbell, 2013-08-13 18:12:40]

For readability, would it be better to use int32 instead of int?

"The IDL says long. Why does the header say int? Is this a bug?" => the reader
needs to go off and read
http://en.wikipedia.org/wiki/64-bit_computing#64-bit_data_models and understand
that sizeof(long) varies across architectures/compilers/OS, and
http://dev.w3.org/2006/webapi/WebIDL/#idl-long to understand that an IDL long is
32 bits.

"The IDL says long. The header says int32" => the reader (correctly) assumes
that IDL long is 32 bits.

(Assuming the reader is at all like me, at least.)