Sync core/timing/ interfaces with their specs, or lack thereof

Source/core/timing/Performance.idl

Index: Source/core/timing/Performance.idl
diff --git a/Source/core/timing/Performance.idl b/Source/core/timing/Performance.idl
index 2c04c8a2c45554cb3b5e7cffbc466fb768024c9b..6a8fab6b0030ec60e72d6f7d0230919d69f66bae 100644
--- a/Source/core/timing/Performance.idl
+++ b/Source/core/timing/Performance.idl
@@ -29,33 +29,53 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-// See: http://www.w3.org/TR/navigation-timing/
+// https://w3c.github.io/hr-time/#the-performance-interface
+
+// TODO(philipj): This interface should be [Exposed=(Window,Worker)]. Doing that
+// would allow the WorkerPerformance interface to be merged into this.
+// TODO(philipj): None of the optional DOMString arguments in this interface
+// should have a default value.
 interface Performance : EventTarget {
-    readonly attribute PerformanceNavigation navigation;
-    readonly attribute PerformanceTiming timing;
-    readonly attribute MemoryInfo memory;
+    DOMHighResTimeStamp now();
 
-    [MeasureAs=UnprefixedPerformanceTimeline] sequence<PerformanceEntry> getEntries();
-    [MeasureAs=UnprefixedPerformanceTimeline] sequence<PerformanceEntry> getEntriesByType(DOMString entryType);
-    [MeasureAs=UnprefixedPerformanceTimeline] sequence<PerformanceEntry> getEntriesByName(DOMString name, optional DOMString entryType = null);
+    // Performance Timeline
+    // https://w3c.github.io/performance-timeline/#the-performance-interface
+    // TODO(philipj): getEntries() should take an optional FilterOptions argument.
+    [MeasureAs=UnprefixedPerformanceTimeline] PerformanceEntryList getEntries();
+    [MeasureAs=UnprefixedPerformanceTimeline] PerformanceEntryList getEntriesByType(DOMString entryType);
+    [MeasureAs=UnprefixedPerformanceTimeline] PerformanceEntryList getEntriesByName(DOMString name, optional DOMString entryType = null);
 
+    // Resource Timing
+    // https://w3c.github.io/resource-timing/#extensions-performance-interface
+    // TODO(philipj): Unprefix these APIs.
     [MeasureAs=PrefixedPerformanceClearResourceTimings] void webkitClearResourceTimings();
     [MeasureAs=PrefixedPerformanceSetResourceTimingBufferSize] void webkitSetResourceTimingBufferSize(unsigned long maxSize);
-
-    [MeasureAs=PerformanceFrameTiming,RuntimeEnabled=FrameTimingSupport] void clearFrameTimings();
-    [MeasureAs=PerformanceFrameTiming,RuntimeEnabled=FrameTimingSupport] void setFrameTimingBufferSize(unsigned long maxSize);
-
     attribute EventHandler onwebkitresourcetimingbufferfull;
 
-    [RuntimeEnabled=FrameTimingSupport] attribute EventHandler onframetimingbufferfull;
+    // Navigation Timing
+    // http://www.w3.org/TR/navigation-timing/#sec-window.performance-attribute
+    // TODO(philipj): The Navigation Timing Rec. defines the (not partial)
+    // Performance interface, while https://w3c.github.io/navigation-timing/ has
+    // changed the interface in an incompatible way:
+    // https://github.com/w3c/navigation-timing/issues/22
+    [Measure] readonly attribute PerformanceTiming timing;
+    [Measure] readonly attribute PerformanceNavigation navigation;
 
-    // See http://www.w3.org/TR/2012/CR-user-timing-20120726/
-    [RaisesException,MeasureAs=UnprefixedUserTiming] void mark(DOMString markName);
+    // User Timing
+    // https://w3c.github.io/user-timing/#extensions-performance-interface
+    [MeasureAs=UnprefixedUserTiming, RaisesException] void mark(DOMString markName);
     [MeasureAs=UnprefixedUserTiming] void clearMarks(optional DOMString markName = null);
 
-    [RaisesException,MeasureAs=UnprefixedUserTiming] void measure(DOMString measureName, optional DOMString startMark = null, optional DOMString endMark = null);
+    [MeasureAs=UnprefixedUserTiming, RaisesException] void measure(DOMString measureName, optional DOMString startMark = null, optional DOMString endMark = null);
     [MeasureAs=UnprefixedUserTiming] void clearMeasures(optional DOMString measureName = null);
 
-    // See http://www.w3.org/TR/hr-time/ for details.
-    double now();
+    // Frame Timing
+    // https://w3c.github.io/frame-timing/#extensions-performance-interface
+    [RuntimeEnabled=FrameTimingSupport, MeasureAs=PerformanceFrameTiming] void clearFrameTimings();
+    [RuntimeEnabled=FrameTimingSupport, MeasureAs=PerformanceFrameTiming] void setFrameTimingBufferSize(unsigned long maxSize);
+    [RuntimeEnabled=FrameTimingSupport] attribute EventHandler onframetimingbufferfull;
+
+    // TODO(philipj): There is no spec for the Memory Info API, see blink-dev:
+    // https://groups.google.com/a/chromium.org/d/msg/blink-dev/g5YRCGpC9vs/b4OJz71NmPwJ
+    [Measure] readonly attribute MemoryInfo memory;
 };