Improve exception messages for detached Range objects.

Improve exception messages for detached Range objects.

Calling a variety of methods on detached Range objects will throw
InvalidStateError. This patch adds some detail to the exception message
in the hopes of informing developers about their errors.

BUG=270033
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=158268

[Mike West, 2013-09-23 12:22:10]

Moar exception error message improvements. Mind taking a look, Alexis?

-mike

[Mike West, 2013-09-24 08:40:19]

Alexis is blinkon-ing. </jealous>

Jochen, mind taking a look?

-mike

[jochen (gone - plz use gerrit), 2013-09-24 09:12:40]

lgtm

[commit-bot: I haz the power, 2013-09-24 09:17:44]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mkwst@chromium.org/23964014/5001

[commit-bot: I haz the power, 2013-09-24 12:24:50]

Change committed as 158268