Add layout tests to check Accept request header values observed by Service Worker

Add layout tests to check Accept request header values observed by Service Worker

BUG=

[hiroshige, 2016-04-11 06:03:52]

hiroshige@chromium.org changed reviewers:
+ falken@chromium.org, nhiroki@chromium.org

[hiroshige, 2016-04-11 06:03:52]

Accept header values in the spec (https://fetch.spec.whatwg.org/#fetching) are
recommended values (indicated by the word 'should' e.g. in 'a user agent
*should* set value'), and this CL tests Accept header values against the values
used by Chromium (which are different from the values in the spec).

Should these tests be placed under chromium/ directory?

[nhiroki, 2016-04-11 08:33:29]

https://codereview.chromium.org/1853333005/diff/1/third_party/WebKit/LayoutTe...
File third_party/WebKit/LayoutTests/http/tests/serviceworker/fetch-event.html
(right):

https://codereview.chromium.org/1853333005/diff/1/third_party/WebKit/LayoutTe...
third_party/WebKit/LayoutTests/http/tests/serviceworker/fetch-event.html:125:
frame.remove();
Thanks to (*), an iframe created by with_iframe() is now automatically removed
at the end of tests and you don't have to explicitly call frame.remove()
anymore.

(*) https://codereview.chromium.org/1859343002/

https://codereview.chromium.org/1853333005/diff/1/third_party/WebKit/LayoutTe...
File
third_party/WebKit/LayoutTests/http/tests/serviceworker/fetch-request-resources.html
(right):

https://codereview.chromium.org/1853333005/diff/1/third_party/WebKit/LayoutTe...
third_party/WebKit/LayoutTests/http/tests/serviceworker/fetch-request-resources.html:14:
var accept_image = 'image/webp,image/*,*/*;q=0.8';
If there is a bug about lack of the "q=0.5" part, can you add a link to that?

https://codereview.chromium.org/1853333005/diff/1/third_party/WebKit/LayoutTe...
third_party/WebKit/LayoutTests/http/tests/serviceworker/fetch-request-resources.html:171:
'`Accept` header value of ' + expected.message +  ' must be ' +
Can you wrap this line at 80th column?

[nhiroki, 2016-04-11 08:37:42]

On 2016/04/11 06:03:52, hiroshige wrote:
> Accept header values in the spec (https://fetch.spec.whatwg.org/#fetching) are
> recommended values (indicated by the word 'should' e.g. in 'a user agent
> *should* set value'), and this CL tests Accept header values against the
values
> used by Chromium (which are different from the values in the spec).
> 
> Should these tests be placed under chromium/ directory?

I think so because webp is supported only in chromium...