[bindings] Implement an ExperimentEnabled IDL extended attribute.

third_party/WebKit/Source/core/experiments/Experiments.h

Index: third_party/WebKit/Source/core/experiments/Experiments.h
diff --git a/third_party/WebKit/Source/core/experiments/Experiments.h b/third_party/WebKit/Source/core/experiments/Experiments.h
index 868a6301cf52352c76602cd908c7cee1eeeae6d6..455558c1000e712c8f3d2aaa6e14953b1790b0a2 100644
--- a/third_party/WebKit/Source/core/experiments/Experiments.h
+++ b/third_party/WebKit/Source/core/experiments/Experiments.h
@@ -25,6 +25,7 @@ namespace blink {
 class CORE_EXPORT Experiments {
 public:
     static bool isApiEnabled(ExecutionContext*, const String& apiName, String& errorMessage);
+    static bool isApiEnabledWithoutMessage(ExecutionContext*, const String& apiName);

[haraken, 2015/12/18 02:35:51]

I'd prefer:

- isAPIEnabled (two args version) calls isAPIEnabledInternal
- isAPIEnabled (three args version) calls isAPIEnabledInternal

[Daniel Nishi, 2015/12/18 05:11:42]

Done.

     // Creates a NotSupportedError exception with a message explaining to
     // external developers why the API is disabled and how to join API
     // experiments.