Try to be more consistent in how we capitalize things. Both the "Title
Case" and "Sentence case" styles are popular, so either would work.
Google and Mozilla both prefer "Sentence case", so let's follow them.
When the error handler itself causes an exception, it falls back to a
simple document.write(). This means the proper error dialog isn't shown
when this happens.
The focus changes that were added to the error handler in e1f8232b are
not crucial for its function. If these focus changes causes an exception
we can just ignore that.
When this error is shown, something has gone very wrong. It shows when
a bug in the JavaScript causes an uncaught error. In these scenarios we
dont want the user to be able to interact with the GUI or the remote
session, since we can't guarantee that things work.
It seems that Firefox has a bug where these are fired incorrectly when
we are in an <iframe>. The events also contain no useful details, so we
can't really do anything useful with them anyway.
This commit moves the global error handler into a separate file,
so that it can catch module loading errors.
This also adds support for properly displaying error messages with
newlines in them (since the module loader may throw those)
