DevTools: Do not force style sheets update on inspector start.

Source/core/inspector/InspectorCSSAgent.h

Index: Source/core/inspector/InspectorCSSAgent.h
diff --git a/Source/core/inspector/InspectorCSSAgent.h b/Source/core/inspector/InspectorCSSAgent.h
index f4768ff85f553e9b09b25918d3fd9267c0b38f3b..90529a9d07cec33624e5c93d5703d50c66b41280 100644
--- a/Source/core/inspector/InspectorCSSAgent.h
+++ b/Source/core/inspector/InspectorCSSAgent.h
@@ -77,6 +77,11 @@ public:
         MediaListSourceImportRule
     };
 
+    enum StyleSheetsUpdateType {
+        InitialFrontendLoad = 0,
+        ExistingFrontendRefresh,
+    };
+
     class InlineStyleOverrideScope {
     public:
         InlineStyleOverrideScope(SecurityContext* context)
@@ -176,7 +181,7 @@ private:
     void collectAllDocumentStyleSheets(Document*, Vector<CSSStyleSheet*>&);
     void collectStyleSheets(CSSStyleSheet*, Vector<CSSStyleSheet*>&);
 
-    void updateActiveStyleSheets(Document*, const Vector<CSSStyleSheet*>&);
+    void updateActiveStyleSheets(Document*, const Vector<CSSStyleSheet*>&, StyleSheetsUpdateType);
 
     void collectPlatformFontsForRenderer(RenderText*, HashCountedSet<String>*);