Add use counters for lots of DOM APIs.

third_party/WebKit/Source/core/timing/PerformanceTiming.idl

Index: third_party/WebKit/Source/core/timing/PerformanceTiming.idl
diff --git a/third_party/WebKit/Source/core/timing/PerformanceTiming.idl b/third_party/WebKit/Source/core/timing/PerformanceTiming.idl
index 19c65ad4865ec7093aafc42a6bddf2f12cfdc7a1..c7cdf0853b626ee5920280edfd3f0fb9c94fe692 100644
--- a/third_party/WebKit/Source/core/timing/PerformanceTiming.idl
+++ b/third_party/WebKit/Source/core/timing/PerformanceTiming.idl
@@ -35,26 +35,26 @@
 [
     Exposed=Window,
 ] interface PerformanceTiming {
-    readonly attribute unsigned long long navigationStart;
-    readonly attribute unsigned long long unloadEventStart;
-    readonly attribute unsigned long long unloadEventEnd;
-    readonly attribute unsigned long long redirectStart;
-    readonly attribute unsigned long long redirectEnd;
-    readonly attribute unsigned long long fetchStart;
-    readonly attribute unsigned long long domainLookupStart;
-    readonly attribute unsigned long long domainLookupEnd;
-    readonly attribute unsigned long long connectStart;
-    readonly attribute unsigned long long connectEnd;
-    readonly attribute unsigned long long secureConnectionStart;
-    readonly attribute unsigned long long requestStart;
-    readonly attribute unsigned long long responseStart;
-    readonly attribute unsigned long long responseEnd;
-    readonly attribute unsigned long long domLoading;
-    readonly attribute unsigned long long domInteractive;
-    readonly attribute unsigned long long domContentLoadedEventStart;
-    readonly attribute unsigned long long domContentLoadedEventEnd;
-    readonly attribute unsigned long long domComplete;
-    readonly attribute unsigned long long loadEventStart;
-    readonly attribute unsigned long long loadEventEnd;
+    [Measure] readonly attribute unsigned long long navigationStart;
+    [Measure] readonly attribute unsigned long long unloadEventStart;
+    [Measure] readonly attribute unsigned long long unloadEventEnd;
+    [Measure] readonly attribute unsigned long long redirectStart;
+    [Measure] readonly attribute unsigned long long redirectEnd;
+    [Measure] readonly attribute unsigned long long fetchStart;
+    [Measure] readonly attribute unsigned long long domainLookupStart;
+    [Measure] readonly attribute unsigned long long domainLookupEnd;
+    [Measure] readonly attribute unsigned long long connectStart;
+    [Measure] readonly attribute unsigned long long connectEnd;
+    [Measure] readonly attribute unsigned long long secureConnectionStart;
+    [Measure] readonly attribute unsigned long long requestStart;
+    [Measure] readonly attribute unsigned long long responseStart;
+    [Measure] readonly attribute unsigned long long responseEnd;
+    [Measure] readonly attribute unsigned long long domLoading;
+    [Measure] readonly attribute unsigned long long domInteractive;
+    [Measure] readonly attribute unsigned long long domContentLoadedEventStart;
+    [Measure] readonly attribute unsigned long long domContentLoadedEventEnd;
+    [Measure] readonly attribute unsigned long long domComplete;
+    [Measure] readonly attribute unsigned long long loadEventStart;
+    [Measure] readonly attribute unsigned long long loadEventEnd;
     serializer = {attribute};
 };