Use high precision timestamp for Event.timestamp

third_party/WebKit/Source/core/timing/PerformanceBase.cpp

Index: third_party/WebKit/Source/core/timing/PerformanceBase.cpp
diff --git a/third_party/WebKit/Source/core/timing/PerformanceBase.cpp b/third_party/WebKit/Source/core/timing/PerformanceBase.cpp
index ad653c600a557a110a2ed88b301a6fd6c0e36149..bed17a883a8353edb1bcc4fbd2b770642adcdf5f 100644
--- a/third_party/WebKit/Source/core/timing/PerformanceBase.cpp
+++ b/third_party/WebKit/Source/core/timing/PerformanceBase.cpp
@@ -422,10 +422,15 @@ double PerformanceBase::clampTimeResolution(double timeSeconds)
     return floor(timeSeconds / resolutionSeconds) * resolutionSeconds;
 }
 
-double PerformanceBase::now() const
+DOMHighResTimeStamp PerformanceBase::monotonicTimeToDOMHighResTimeStamp(double monotonicTime) const
 {
-    double nowSeconds = monotonicallyIncreasingTime() - m_timeOrigin;
-    return 1000.0 * clampTimeResolution(nowSeconds);
+    double timeInSeconds = monotonicTime - m_timeOrigin;
+    return convertSecondsToDOMHighResTimeStamp(clampTimeResolution(timeInSeconds));
+}
+
+DOMHighResTimeStamp PerformanceBase::now() const
+{
+    return monotonicTimeToDOMHighResTimeStamp(monotonicallyIncreasingTime()); // in milliseconds

[Rick Byers, 2015/09/29 15:57:59]

nit: this comment seems redundant (it's clear you're going to
DOMHighRestTimestamp - comments on units like this are necessary as a hack only
when using plain numeric types).

[majidvp, 2015/10/01 20:57:19]

Done.

 }
 
 DEFINE_TRACE(PerformanceBase)