Return ERR_INVALID_RESPONSE when we get a funky error page mime-type.

Return ERR_INVALID_RESPONSE when we get a funky error page mime-type.
ERR_FILE_NOT_FOUND was being returned before, which is rather
misleading.

ERR_INVALID_RESPONSE is a very rare error, and currently just uses the
generic error page, with no strings of its own.  If this CL significantly
increases the frequency of the error, we should add strings for it.

BUG=344633
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=252163

[mmenke, 2014-02-19 20:16:14]

A Googler pointed out to me how little sense this error code made.  The new code
isn't exactly illuminating, but at least it indicates the server did, in fact,
respond.

This funky error code has been returned since initial.commit.

[davidben, 2014-02-19 20:18:43]

On 2014/02/19 20:16:14, mmenke wrote:
> A Googler pointed out to me how little sense this error code made.  The new
code
> isn't exactly illuminating, but at least it indicates the server did, in fact,
> respond.
> 
> This funky error code has been returned since initial.commit.

LGTM.

What a bizarre case to ever come across...

[mmenke, 2014-02-19 20:20:14]

The CQ bit was checked by mmenke@chromium.org

[mmenke, 2014-02-19 20:23:45]

On 2014/02/19 20:18:43, David Benjamin wrote:
> On 2014/02/19 20:16:14, mmenke wrote:
> > A Googler pointed out to me how little sense this error code made.  The new
> code
> > isn't exactly illuminating, but at least it indicates the server did, in
fact,
> > respond.
> > 
> > This funky error code has been returned since initial.commit.
> 
> LGTM.
> 
> What a bizarre case to ever come across...

Hmm....  Do you "come across" a case if the problem is with your own server?  :)

[commit-bot: I haz the power, 2014-02-19 20:25:10]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mmenke@chromium.org/165983007/220001

[mmenke, 2014-02-19 22:29:12]

The CQ bit was unchecked by mmenke@chromium.org

[mmenke, 2014-02-19 22:29:17]

The CQ bit was checked by mmenke@chromium.org

[commit-bot: I haz the power, 2014-02-20 00:22:16]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mmenke@chromium.org/165983007/220001

[commit-bot: I haz the power, 2014-02-20 02:29:12]

Change committed as 252163