Fix first paint tracking for SPv2

third_party/WebKit/Source/core/paint/ViewPainter.cpp

Index: third_party/WebKit/Source/core/paint/ViewPainter.cpp
diff --git a/third_party/WebKit/Source/core/paint/ViewPainter.cpp b/third_party/WebKit/Source/core/paint/ViewPainter.cpp
index ac91a1edeb46d394339a162e1c8b620093905389..2d3ac26d80527cf1138313cacbc200fadde28876 100644
--- a/third_party/WebKit/Source/core/paint/ViewPainter.cpp
+++ b/third_party/WebKit/Source/core/paint/ViewPainter.cpp
@@ -167,12 +167,10 @@ void ViewPainter::paintBoxDecorationBackground(const PaintInfo& paintInfo) {
       shouldDrawBackgroundInSeparateBuffer
           ? rootBackgroundColor
           : baseBackgroundColor.blend(rootBackgroundColor);
-  if (combinedBackgroundColor != frameView.baseBackgroundColor() &&
-      !context.getPaintController().nonDefaultBackgroundColorPainted()) {
-    TRACE_EVENT_INSTANT0("blink.user_timing", "paintNonDefaultBackgroundColor",
-                         TRACE_EVENT_SCOPE_GLOBAL);
-    context.getPaintController().setNonDefaultBackgroundColorPainted();
-  }
+
+  if (combinedBackgroundColor != frameView.baseBackgroundColor())
+    context.getPaintController().setFirstPainted();
+
   if (combinedBackgroundColor.alpha()) {
     if (!combinedBackgroundColor.hasAlpha() &&
         RuntimeEnabledFeatures::slimmingPaintV2Enabled())