Revert of Added DCHECK for monotonicTimeToDOMHighResTimeStamp in PerformanceBase

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 56b483ab38a210a0bec60bacb403af346bc259f6..04e8fc0b0b398e32535bdb89324120857e360e88 100644
--- a/third_party/WebKit/Source/core/timing/PerformanceBase.cpp
+++ b/third_party/WebKit/Source/core/timing/PerformanceBase.cpp
@@ -580,7 +580,8 @@ DOMHighResTimeStamp PerformanceBase::monotonicTimeToDOMHighResTimeStamp(
     return 0.0;
 
   double timeInSeconds = monotonicTime - timeOrigin;
-  DCHECK_GE(timeInSeconds, 0);
+  if (timeInSeconds < 0)
+    return 0.0;
   return convertSecondsToDOMHighResTimeStamp(
       clampTimeResolution(timeInSeconds));
 }