Changed the css feature name trace string to avoid collisions

third_party/WebKit/Source/core/frame/UseCounter.cpp

Index: third_party/WebKit/Source/core/frame/UseCounter.cpp
diff --git a/third_party/WebKit/Source/core/frame/UseCounter.cpp b/third_party/WebKit/Source/core/frame/UseCounter.cpp
index 01d9148d76276539228965b0d1fae360e637e1b0..e07d0d6b9110505a6afa5d2b79d1a10f9236ae41 100644
--- a/third_party/WebKit/Source/core/frame/UseCounter.cpp
+++ b/third_party/WebKit/Source/core/frame/UseCounter.cpp
@@ -1230,7 +1230,7 @@ void UseCounter::count(CSSParserMode cssParserMode, CSSPropertyID property) {
     // https://github.com/HTTPArchive/httparchive/issues/59
     int sampleId = mapCSSPropertyIdToCSSSampleIdForHistogram(property);
     TRACE_EVENT1(TRACE_DISABLED_BY_DEFAULT("blink.feature_usage"),
-                 "CSSFeatureFirstUsed", "feature", sampleId);
+                 "CSSFirstUsed", "feature", sampleId);
     cssHistogram().count(sampleId);
     m_CSSRecorded.quickSet(property);
   }