[DurableStorage] Add UseCounter and fixed IDL

third_party/WebKit/Source/modules/quota/StorageManager.idl

Index: third_party/WebKit/Source/modules/quota/StorageManager.idl
diff --git a/third_party/WebKit/Source/modules/quota/StorageManager.idl b/third_party/WebKit/Source/modules/quota/StorageManager.idl
index 7e8955bc343c1d7f7b2802ad45a32433781a3df9..0cb214409a6dbb233db67e839bff370521ea2fd1 100644
--- a/third_party/WebKit/Source/modules/quota/StorageManager.idl
+++ b/third_party/WebKit/Source/modules/quota/StorageManager.idl
@@ -6,10 +6,10 @@
 
 [
     Exposed=(Window,Worker),
-    RuntimeEnabled=DurableStorage,
+    OriginTrialEnabled=DurableStorage,
 ] interface StorageManager {
-    [CallWith=ScriptState] Promise<boolean> persisted();
-    [Exposed=Window, CallWith=ScriptState] Promise<boolean> persist();
+    [CallWith=ScriptState, MeasureAs=DurableStoragePersisted] Promise<boolean> persisted();
+    [Exposed=Window, CallWith=ScriptState, MeasureAs=DurableStoragePersist] Promise<boolean> persist();
 
-    [RuntimeEnabled=StorageEstimate, CallWith=ScriptState] Promise<StorageEstimate> estimate();
+    [RuntimeEnabled=StorageEstimate, CallWith=ScriptState, MeasureAs=DurableStorageEstimate] Promise<StorageEstimate> estimate();

[chasej, 2016/05/17 03:00:42]

Given that estimate() isn't being exposed as part of the origin trial, this
method doesn't need [MeasureAs] for that reason. I think it's certainly
reasonable to add it now. I'm just mentioning in case there was confusion.

 };