Only need to re-evaluate MQ on resize.

Source/core/frame/FrameView.cpp

Index: Source/core/frame/FrameView.cpp
diff --git a/Source/core/frame/FrameView.cpp b/Source/core/frame/FrameView.cpp
index 6633b1be6850dcd7980e7b7834dfd6b6f8b44d55..82df1a4b4f298f20497c06059b0b5e073a868040 100644
--- a/Source/core/frame/FrameView.cpp
+++ b/Source/core/frame/FrameView.cpp
@@ -816,15 +816,16 @@ void FrameView::performPreLayoutTasks()
         m_inSynchronousPostLayout = false;
     }
 
+    bool wasResized = wasViewportResized();
     Document* document = m_frame->document();
-    if (wasViewportResized())
+    if (wasResized)
         document->notifyResizeForViewportUnits();
 
     // Viewport-dependent media queries may cause us to need completely different style information.
-    if (!document->styleResolver() || document->styleResolver()->mediaQueryAffectedByViewportChange()) {
+    if (!document->styleResolver() || (wasResized && document->styleResolver()->mediaQueryAffectedByViewportChange())) {
         document->styleResolverChanged();
         document->mediaQueryAffectingValueChanged();
-    } else {
+    } else if (wasResized) {
         document->evaluateMediaQueryList();
     }