Add disabled origin trial feature list

third_party/WebKit/Source/core/origin_trials/OriginTrialContext.cpp

Index: third_party/WebKit/Source/core/origin_trials/OriginTrialContext.cpp
diff --git a/third_party/WebKit/Source/core/origin_trials/OriginTrialContext.cpp b/third_party/WebKit/Source/core/origin_trials/OriginTrialContext.cpp
index a5a268fbb0a580c98c9b4c95175823c4970ca3d3..2822147229d58cbfd111c25bea3c44d573b80ee4 100644
--- a/third_party/WebKit/Source/core/origin_trials/OriginTrialContext.cpp
+++ b/third_party/WebKit/Source/core/origin_trials/OriginTrialContext.cpp
@@ -80,7 +80,8 @@ int getTokenValidationResultPriority(
     //   5. Wrong version for token (not currently supported version number(s))
     //   6. Invalid data in token (can be before/after validating signature)
     //   7. Embedder does not support origin trials
-    //   8. No tokens provided
+    //   8. The feature requested is disabled

[chasej, 2016/06/08 16:14:24]

I'd argue that FeatureDisabled has the highest priority over any token failures
(especially since the implementation checks this first, and ignores the token).

Taking it one step further, maybe should optimize checkFeatureEnabled() to stop
checking tokens if this failure is encountered.

[iclelland, 2016/06/08 17:43:44]

That's not what this priority sequence represents, though, is it? No Tokens is
checked first, technically, and Expired is checked very late. The fact that a
token made it almost all the way to the end of the validation sequence means
that a failure at that point is the highest priority in terms of choosing a
message for the user.

In practice, though, it doesn't matter -- FeatureDisabled is never going to be
compared to any of the other validation failures.
The optimization is a good idea, since it's just a waste of time checking
further if the policy said to disable the feature.
Given that, I've been able to just remove FeatureDisabled from the priority list
above.

+    //   9. No tokens provided
     // NOTE: Lower numbers are higher priority
     // See this document for details:
     // https://docs.google.com/document/d/1qVP2CK1lbfmtIJRIm6nwuEFFhGhYbtThLQPo3CSTtmg/edit#bookmark=id.k1j0q938so3b
@@ -104,8 +105,10 @@ int getTokenValidationResultPriority(
         return 6;
     case WebOriginTrialTokenStatus::NotSupported:
         return 7;
-    case WebOriginTrialTokenStatus::NoTokens:
+    case WebOriginTrialTokenStatus::FeatureDisabled:
         return 8;
+    case WebOriginTrialTokenStatus::NoTokens:
+        return 9;
     }
 
     NOTREACHED();