Use WTF::TimeTicks to represent timestamp in Platform/Core event types

third_party/WebKit/Source/core/events/Event.cpp

Index: third_party/WebKit/Source/core/events/Event.cpp
diff --git a/third_party/WebKit/Source/core/events/Event.cpp b/third_party/WebKit/Source/core/events/Event.cpp
index 7f0f5a312e6469d97e5cb97af592b7d0d2c4262b..127454d08936cc410d276ac9fa024a725086cbe0 100644
--- a/third_party/WebKit/Source/core/events/Event.cpp
+++ b/third_party/WebKit/Source/core/events/Event.cpp
@@ -30,7 +30,6 @@
 #include "core/svg/SVGElement.h"
 #include "core/timing/DOMWindowPerformance.h"
 #include "core/timing/Performance.h"
-#include "wtf/CurrentTime.h"
 
 namespace blink {
 
@@ -57,7 +56,7 @@ Event::Event() : Event("", false, false) {
 Event::Event(const AtomicString& eventType,
              bool canBubbleArg,
              bool cancelableArg,
-             double platformTimeStamp)
+             TimeTicks platformTimeStamp)
     : Event(eventType,
             canBubbleArg,
             cancelableArg,
@@ -72,13 +71,13 @@ Event::Event(const AtomicString& eventType,
             canBubbleArg,
             cancelableArg,
             composedMode,
-            monotonicallyIncreasingTime()) {}
+            TimeTicks::Now()) {}
 
 Event::Event(const AtomicString& eventType,
              bool canBubbleArg,
              bool cancelableArg,
              ComposedMode composedMode,
-             double platformTimeStamp)
+             TimeTicks platformTimeStamp)
     : m_type(eventType),
       m_canBubble(canBubbleArg),
       m_cancelable(cancelableArg),
@@ -103,7 +102,7 @@ Event::Event(const AtomicString& eventType, const EventInit& initializer)
             initializer.cancelable(),
             initializer.composed() ? ComposedMode::Composed
                                    : ComposedMode::Scoped,
-            monotonicallyIncreasingTime()) {}
+            TimeTicks::Now()) {}
 
 Event::~Event() {}
 
@@ -332,8 +331,9 @@ double Event::timeStamp(ScriptState* scriptState) const {
   if (scriptState && scriptState->domWindow()) {
     Performance* performance =
         DOMWindowPerformance::performance(*scriptState->domWindow());
+    double timestampSeconds = (m_platformTimeStamp - TimeTicks()).InSecondsF();
     timeStamp =
-        performance->monotonicTimeToDOMHighResTimeStamp(m_platformTimeStamp);
+        performance->monotonicTimeToDOMHighResTimeStamp(timestampSeconds);
   }
 
   return timeStamp;