Support full range of PreflightPolicy over WebURLLoaderOptions

Support full range of PreflightPolicy over WebURLLoaderOptions

Allow users of WebURLLoader to state the preflight behavior to follow
for the request. This is done so that the user/caller can explicitly
control when its author header set
(http://www.w3.org/TR/cors/#author-request-headers) is empty, then no
preflight must be performed.

This puts the responsibility on the caller to adhere to CORS and not
disable preflighting when the author set is non-empty or the request
is over non-simple methods (http://www.w3.org/TR/cors/#simple-method )

The WebURLLoaderOptions default is ConsiderPreflight.

R=jochen
BUG=173727
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=162225

[sof, 2013-11-18 09:43:53]

At your leisure, please have a look.

For context, https://code.google.com/p/chromium/issues/detail?id=173727#c10

[jochen (gone - plz use gerrit), 2013-11-18 11:59:06]

lgtm

https://codereview.chromium.org/68173029/diff/1/Source/web/AssociatedURLLoade...
File Source/web/AssociatedURLLoader.cpp (right):

https://codereview.chromium.org/68173029/diff/1/Source/web/AssociatedURLLoade...
Source/web/AssociatedURLLoader.cpp:311:
COMPILE_ASSERT_MATCHING_ENUM(WebURLLoaderOptions::CrossOriginRequestPolicyAllow,
AllowCrossOriginRequests);
please add new enums here

[sof, 2013-11-18 12:28:08]

On 2013/11/18 11:59:06, jochen wrote:
> lgtm
> 
>
https://codereview.chromium.org/68173029/diff/1/Source/web/AssociatedURLLoade...
> File Source/web/AssociatedURLLoader.cpp (right):
> 
>
https://codereview.chromium.org/68173029/diff/1/Source/web/AssociatedURLLoade...
> Source/web/AssociatedURLLoader.cpp:311:
>
COMPILE_ASSERT_MATCHING_ENUM(WebURLLoaderOptions::CrossOriginRequestPolicyAllow,
> AllowCrossOriginRequests);
> please add new enums here

Done; thanks.

[commit-bot: I haz the power, 2013-11-18 18:33:33]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/sigbjornf@opera.com/68173029/60001

[commit-bot: I haz the power, 2013-11-18 19:38:46]

Change committed as 162225