Collect UMA data for Origin Trials

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

Index: third_party/WebKit/Source/core/origin_trials/OriginTrialContext.h
diff --git a/third_party/WebKit/Source/core/origin_trials/OriginTrialContext.h b/third_party/WebKit/Source/core/origin_trials/OriginTrialContext.h
index 1b4b6772a2957519e527e8b250413092b5d323fa..80550e0f321b08ae8a2b60fc2827b80a97ae5f88 100644
--- a/third_party/WebKit/Source/core/origin_trials/OriginTrialContext.h
+++ b/third_party/WebKit/Source/core/origin_trials/OriginTrialContext.h
@@ -17,20 +17,20 @@ namespace blink {
 class ExecutionContext;
 class WebTrialTokenValidator;
 
-// The Experimental Framework (EF) provides limited access to experimental
-// features, on a per-origin basis (origin trials). This class provides the
-// implementation to check if the experimental feature should be enabled for the
-// current context.  This class is not for direct use by feature implementers.
+// The Origin Trials Framework provides limited access to experimental features,
+// on a per-origin basis (origin trials). This class provides the implementation
+// to check if the experimental feature should be enabled for the current
+// context.  This class is not for direct use by feature implementers.
 // Instead, the OriginTrials generated namespace provides a method for each
 // feature to check if it is enabled. Experimental features must be defined in
 // RuntimeEnabledFeatures.in, which is used to generate OriginTrials.h/cpp.
 //
 // Experimental features are defined by string names, provided by the
-// implementers. The EF code does not maintain an enum or constant list for
-// feature names. Instead, the EF validates the name provided by the feature
-// implementation against any provided tokens.
+// implementers. The framework does not maintain an enum or constant list for
+// feature names. Instead, the name provided by the feature implementation
+// is validated against any provided tokens.
 //
-// TODO(chasej): Link to documentation, or provide more detail on keys, .etc
+// For more information, see https://github.com/jpchase/OriginTrials.
 class CORE_EXPORT OriginTrialContext final : public GarbageCollectedFinalized<OriginTrialContext>, public Supplement<ExecutionContext> {
 USING_GARBAGE_COLLECTED_MIXIN(OriginTrialContext)
 public:
@@ -53,6 +53,13 @@ private:
     Member<ExecutionContext> m_host;
     Vector<String> m_tokens;
 
+    int checkFeatureEnabled(const String& featureName, String* errorMessage, WebTrialTokenValidator* = nullptr);
+
+    // Records whether metrics about the enabled status have been recorded, for
+    // each feature name. Only one result should be recorded per context,
+    // regardless of how many times the enabled check is actually done.
+    HashSet<String> m_enabledResultCountedForFeature;
+
     // Records whether an error message has been generated, for each feature
     // name. Since these messages are generally written to the console, this is
     // used to avoid cluttering the console with messages on every access.