Move Referrer into CommonParamTraits

Move Referrer into CommonParamTraits

While working on http://codereview.chromium.org/9875026/ , I ended up needing to put a content::Referrer into the prerender_messages.  The problem was that it's already used in view_messages, and the compile would fail due to duplicate definitions.  The CommonParamTraits approach here avoids this problem by explicitly including a serializer and deserializer.

BUG=None

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=133915

[gavinp, 2012-04-22 22:26:13]

John,

I'm not totally happy with this solution; but it does avoid the issue I found in
the description.  I couldn't find instances of objects used in multiple types of
messages that weren't in the CommonParamTraits.

Is there a better way to do this?  Should we have a TODO from this?  Or is this
just fine?  WDYT?

[jam, 2012-04-23 15:25:40]

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
File content/public/common/common_param_traits.cc (right):

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
content/public/common/common_param_traits.cc:13: #include
"third_party/WebKit/Source/Platform/chromium/public/WebReferrerPolicy.h"
nit: not needed since it's in the header

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
content/public/common/common_param_traits.cc:459: if (!ReadParam(m, iter, &url))
nit: this is usually written as

return ReadParam(m, iter, &r->url) && ReadParam(m, iter, &r->policy);

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
File content/public/common/common_param_traits.h (right):

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
content/public/common/common_param_traits.h:250: struct CONTENT_EXPORT
SimilarTypeTraits<WebKit::WebReferrerPolicy> {
nit: are you sure you need the CONTENT_EXPORT?

[gavinp, 2012-04-23 19:17:41]

Thanks for your review, John.

You'll see some weirdness if you take the delta-from-patch-set view on
view_messages.h; I updated to trunk and what you're seeing there is from trunk. 
My apologies if that's confusing.

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
File content/public/common/common_param_traits.cc (right):

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
content/public/common/common_param_traits.cc:13: #include
"third_party/WebKit/Source/Platform/chromium/public/WebReferrerPolicy.h"
On 2012/04/23 15:25:40, John Abd-El-Malek wrote:
> nit: not needed since it's in the header

Done.

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
content/public/common/common_param_traits.cc:459: if (!ReadParam(m, iter, &url))
On 2012/04/23 15:25:40, John Abd-El-Malek wrote:
> nit: this is usually written as
> 
> return ReadParam(m, iter, &r->url) && ReadParam(m, iter, &r->policy);

Done.  I was apparently overly concerned that when failing to read policy we'll
have mutated the callers |url|, there is clearly no other excuse for all that
mechanism.

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
File content/public/common/common_param_traits.h (right):

http://codereview.chromium.org/10134024/diff/1/content/public/common/common_p...
content/public/common/common_param_traits.h:250: struct CONTENT_EXPORT
SimilarTypeTraits<WebKit::WebReferrerPolicy> {
On 2012/04/23 15:25:40, John Abd-El-Malek wrote:
> nit: are you sure you need the CONTENT_EXPORT?

I do not.  The content::Referrer one is required, as that's what in the chrome
based PrerenderMsg.  The resource messages use this, but they are in content
too, so it is fine.

[gavinp, 2012-04-23 19:25:04]

http://codereview.chromium.org/10134024/diff/8003/content/public/common/commo...
File content/public/common/common_param_traits.h (right):

http://codereview.chromium.org/10134024/diff/8003/content/public/common/commo...
content/public/common/common_param_traits.h:29: #include
"third_party/WebKit/Source/WebKit/chromium/public/WebReferrerPolicy.h"
N.B. This change makes the new upload relative to trunk, instead of a commit
mid-stream developing the Prerendering API.  So try jobs will work, but I need
to update http://codereview.chromium.org/10139023/ if this lands like this.

[jam, 2012-04-23 22:36:59]

lgtm

[commit-bot: I haz the power, 2012-04-25 13:43:01]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/gavinp@chromium.org/10134024/11003

[commit-bot: I haz the power, 2012-04-25 15:05:56]

Change committed as 133915