Collect UMA data for Origin Trials

content/common/origin_trials/trial_token.h

Index: content/common/origin_trials/trial_token.h
diff --git a/content/common/origin_trials/trial_token.h b/content/common/origin_trials/trial_token.h
index fa05e3713b5b943cbd3f8fd774d09f1c5f8793cc..3471fa4eae78087963dc654935ad83b37d16011b 100644
--- a/content/common/origin_trials/trial_token.h
+++ b/content/common/origin_trials/trial_token.h
@@ -11,6 +11,7 @@
 #include "base/strings/string_piece.h"
 #include "base/time/time.h"
 #include "content/common/content_export.h"
+#include "content/common/origin_trials/trial_token_status.h"
 #include "url/origin.h"
 
 namespace content {
@@ -32,19 +33,24 @@ class CONTENT_EXPORT TrialToken {
  public:
   ~TrialToken();
 
-  // Returns a token object if the string represents a signed well-formed token,
-  // or nullptr otherwise. (This does not mean that the token is currently
-  // valid, or appropriate for a given origin / feature, just that it is
+  // If the string represents a signed well-formed token, a token object is
+  // returned, and success is returned in the |out_status| parameter. Otherwise,
+  // the |out_status| parameter indicates what was wrong with the string, and
+  // nullptr is returned.
+  // Note that success does not mean that the token is currently valid, or
+  // appropriate for a given origin / feature. It only means that it is
   // correctly formatted and signed by the supplied public key, and can be
-  // parsed.)
+  // parsed.
   static std::unique_ptr<TrialToken> From(const std::string& token_text,
-                                          base::StringPiece public_key);
+                                          base::StringPiece public_key,
+                                          TrialTokenStatus* out_status);
 
-  // Returns true if this token is appropriate for use by the given origin,
-  // for the given feature name, and has not yet expired.
-  bool IsValidForFeature(const url::Origin& origin,
-                         base::StringPiece feature_name,
-                         const base::Time& now) const;
+  // Returns success if this token is appropriate for use by the given origin
+  // and feature name, and has not yet expired. Otherwise, the return value
+  // indicates why the token is not valid.
+  TrialTokenStatus IsValidForFeature(const url::Origin& origin,
+                                     base::StringPiece feature_name,
+                                     const base::Time& now) const;
 
   url::Origin origin() { return origin_; }
   std::string feature_name() { return feature_name_; }
@@ -53,10 +59,13 @@ class CONTENT_EXPORT TrialToken {
  protected:
   friend class TrialTokenTest;
 
-  // Returns the payload of a signed token, or nullptr if the token is not
-  // properly signed, or is not well-formed.
-  static std::unique_ptr<std::string> Extract(const std::string& token_text,
-                                              base::StringPiece public_key);
+  // If the string represents a properly signed and well-formed token, the JSON
+  // payload is returned in the |out_token_json| parameter and success is
+  // returned. Otherwise,the return code indicates what was wrong with the
+  // string, and |out_token_json| is unchanged.
+  static TrialTokenStatus Extract(const std::string& token_text,
+                                  base::StringPiece public_key,
+                                  std::string* out_token_json);
 
   // Returns a token object if the string represents a well-formed JSON token
   // payload, or nullptr otherwise.