Expose v8::Function::IsBuiltin to public API.

Expose v8::Function::IsBuiltin to public API.

This will be used by DevTools so that we could generate a better preview in console. Namely, we could assume that a preview of an object is lossless if all its member functions are builtin.

We also may want to expose this to DevTools users via remote debugging protocol in Debugger.FunctionDetails struct.

BUG=chromium:261470
R=mstarzinger@chromium.org, yurys@chromium.org, dcarney@chromium.org, yurys

Committed: https://code.google.com/p/v8/source/detail?r=17323

[yurys, 2013-10-17 13:30:25]

Can you add to the description some details on why we need to expose this
through the public API?

[aandrey, 2013-10-17 13:40:16]

On 2013/10/17 13:30:25, Yury Semikhatsky wrote:
> Can you add to the description some details on why we need to expose this
> through the public API?

Done.

[Michael Starzinger, 2013-10-17 15:16:40]

LGTM.

[yurys, 2013-10-18 13:24:05]

Is it possible to detect builtin functions based on their
v8::Function::ScriptId() property?

[aandrey, 2013-10-22 10:05:11]

On 2013/10/18 13:24:05, Yury Semikhatsky wrote:
> Is it possible to detect builtin functions based on their
> v8::Function::ScriptId() property?

Does not seem so. This is how I had to modify my test to make it pass:

  f = v8::Local<v8::Function>::Cast(CompileRun("Math.floor"));
  CHECK_EQ(8, f->ScriptId());
  f = v8::Local<v8::Function>::Cast(CompileRun("Object"));
  CHECK_EQ(0, f->ScriptId());
  f = v8::Local<v8::Function>::Cast(CompileRun("Object.__defineSetter__"));
  CHECK_EQ(4, f->ScriptId());
  f = v8::Local<v8::Function>::Cast(CompileRun("Array.prototype.toString"));
  CHECK_EQ(5, f->ScriptId());
  f = v8::Local<v8::Function>::Cast(CompileRun("function a() {}; a;"));
  CHECK_EQ(21, f->ScriptId());

All script IDs are different.

[yurys, 2013-10-22 12:24:22]

lgtm

[yurys, 2013-10-22 14:50:28]

Committed patchset #1 manually as r17323 (presubmit successful).