Add use counters for lots of DOM APIs.

third_party/WebKit/Source/core/html/track/TextTrackList.idl

Index: third_party/WebKit/Source/core/html/track/TextTrackList.idl
diff --git a/third_party/WebKit/Source/core/html/track/TextTrackList.idl b/third_party/WebKit/Source/core/html/track/TextTrackList.idl
index 78fdaf64fa80c9bbadf3743451793e84ef9f2f14..d80bca1af6c5a77b2da9e0880bf24187c4b39330 100644
--- a/third_party/WebKit/Source/core/html/track/TextTrackList.idl
+++ b/third_party/WebKit/Source/core/html/track/TextTrackList.idl
@@ -28,11 +28,11 @@
 [
     SetWrapperReferenceFrom=owner,
 ] interface TextTrackList : EventTarget {
-    readonly attribute unsigned long length;
-    getter TextTrack (unsigned long index);
-    TextTrack? getTrackById(DOMString id);
+    [Measure] readonly attribute unsigned long length;
+    [Measure] getter TextTrack (unsigned long index);
+    [Measure] TextTrack? getTrackById(DOMString id);
 
-    attribute EventHandler onchange;
-    attribute EventHandler onaddtrack;
-    attribute EventHandler onremovetrack;
+    [Measure] attribute EventHandler onchange;
+    [Measure] attribute EventHandler onaddtrack;
+    [Measure] attribute EventHandler onremovetrack;
 };