Return error information from pdfium to JS.

Return error information from pdfium to JS.

This implements the previously unimplemented JS_Error() function.

Along the way:
- fix some IWYU when the include order in global.cpp was perturbed.
- remove some uses of JS_ErrorString, to increase transparency.
- use vp.IsSetting() in place of !vp.IsGetting() for clarity.
- specify an error string on several error return paths.
- add an error string for writing readonly properties.
- rename an error string constant to reflect the actual message.
- replace calls to variadic Format() with a function doing string appends.
- remove unused JS_GetClassName()

R=thestig@chromium.org

Committed: https://pdfium.googlesource.com/pdfium/+/b720d0a14601f1496ef15297bc46d401f5a2a890

[Tom Sepez, 2015-02-27 23:01:08]

tsepez@chromium.org changed reviewers:
+ thestig@chromium.org

[Tom Sepez, 2015-02-27 23:01:09]

Lei, please review.
Bruce, FYI.

Another step forward for testing sanity.

[Lei Zhang, 2015-02-28 02:50:49]

lgtm with some nits.

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/include/javascri...
File fpdfsdk/include/javascript/JS_Define.h (right):

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/include/javascri...
fpdfsdk/include/javascript/JS_Define.h:50: namespace {
I don't think this stops anyone that includes JS_Define.h from calling
FormatErrorString().

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/src/javascript/D...
File fpdfsdk/src/javascript/Document.cpp (right):

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/src/javascript/D...
fpdfsdk/src/javascript/Document.cpp:19: #include
"../../include/javascript/Field.h"
care to remove this duplicate #include while we are here?

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/src/javascript/g...
File fpdfsdk/src/javascript/global.cpp (right):

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/src/javascript/g...
fpdfsdk/src/javascript/global.cpp:274: CJS_Context* pContext =
static_cast<CJS_Context*>(cc);
The indentation here is inconsistent.

[Tom Sepez, 2015-03-02 19:03:44]

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/include/javascri...
File fpdfsdk/include/javascript/JS_Define.h (right):

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/include/javascri...
fpdfsdk/include/javascript/JS_Define.h:50: namespace {
On 2015/02/28 02:50:49, Lei Zhang wrote:
> I don't think this stops anyone that includes JS_Define.h from calling
> FormatErrorString().

Argh, yeah, I'm in a header.  I'll put this into the newly-added resource.cpp
file.

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/src/javascript/D...
File fpdfsdk/src/javascript/Document.cpp (right):

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/src/javascript/D...
fpdfsdk/src/javascript/Document.cpp:19: #include
"../../include/javascript/Field.h"
On 2015/02/28 02:50:49, Lei Zhang wrote:
> care to remove this duplicate #include while we are here?
You betcha.  I'm going to hold off on sorting these til a follow-up; doing so
usually kicks out more IWYU.

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/src/javascript/g...
File fpdfsdk/src/javascript/global.cpp (right):

https://codereview.chromium.org/963193003/diff/60001/fpdfsdk/src/javascript/g...
fpdfsdk/src/javascript/global.cpp:274: CJS_Context* pContext =
static_cast<CJS_Context*>(cc);
On 2015/02/28 02:50:49, Lei Zhang wrote:
> The indentation here is inconsistent.
Tabs are driving me crazy.

[Lei Zhang, 2015-03-02 20:13:13]

still lgtm

https://codereview.chromium.org/963193003/diff/100001/fpdfsdk/include/javascr...
File fpdfsdk/include/javascript/JS_Define.h (right):

https://codereview.chromium.org/963193003/diff/100001/fpdfsdk/include/javascr...
fpdfsdk/include/javascript/JS_Define.h:43: typedef CFX_WideString
JS_ErrorString;
I thought you were going to move this down to line 49 to be with the other
typedefs.

[Tom Sepez, 2015-03-02 20:16:27]

On 2015/03/02 20:13:13, Lei Zhang wrote:
> still lgtm
> 
>
https://codereview.chromium.org/963193003/diff/100001/fpdfsdk/include/javascr...
> File fpdfsdk/include/javascript/JS_Define.h (right):
> 
>
https://codereview.chromium.org/963193003/diff/100001/fpdfsdk/include/javascr...
> fpdfsdk/include/javascript/JS_Define.h:43: typedef CFX_WideString
> JS_ErrorString;
> I thought you were going to move this down to line 49 to be with the other
> typedefs.
I'm going to kill it in a subsequent CL.  So just to minimize the changed
sections, I left it where it was.  But alas tabs inbetween ...

[Tom Sepez, 2015-03-02 20:17:19]

On 2015/03/02 20:16:27, Tom Sepez wrote:
> On 2015/03/02 20:13:13, Lei Zhang wrote:
> > still lgtm
> > 
> >
>
https://codereview.chromium.org/963193003/diff/100001/fpdfsdk/include/javascr...
> > File fpdfsdk/include/javascript/JS_Define.h (right):
> > 
> >
>
https://codereview.chromium.org/963193003/diff/100001/fpdfsdk/include/javascr...
> > fpdfsdk/include/javascript/JS_Define.h:43: typedef CFX_WideString
> > JS_ErrorString;
> > I thought you were going to move this down to line 49 to be with the other
> > typedefs.
> I'm going to kill it in a subsequent CL.  So just to minimize the changed
> sections, I left it where it was.  But alas tabs inbetween ...
So it moves back.

[Tom Sepez, 2015-03-02 20:18:54]

Committed patchset #7 (id:120001) manually as
b720d0a14601f1496ef15297bc46d401f5a2a890 (tree was closed).