Fix virtual/override/final usage in Source/platform/.

Source/platform/fonts/SegmentedFontData.h

Index: Source/platform/fonts/SegmentedFontData.h
diff --git a/Source/platform/fonts/SegmentedFontData.h b/Source/platform/fonts/SegmentedFontData.h
index 2b77c9207f7a6ca68d56a9ca3ec99cf173f8d6b0..325137e2369de23d8a7f25271e4975513294beae 100644
--- a/Source/platform/fonts/SegmentedFontData.h
+++ b/Source/platform/fonts/SegmentedFontData.h
@@ -57,7 +57,7 @@ class PLATFORM_EXPORT SegmentedFontData : public FontData {
 public:
     static PassRefPtr<SegmentedFontData> create() { return adoptRef(new SegmentedFontData); }
 
-    virtual ~SegmentedFontData();
+    ~SegmentedFontData() override;
 
     void appendRange(const FontDataRange& range) { m_ranges.append(range); }
     unsigned numRanges() const { return m_ranges.size(); }
@@ -67,13 +67,13 @@ public:
 private:
     SegmentedFontData() { }
 
-    virtual const SimpleFontData* fontDataForCharacter(UChar32) const override;
+    const SimpleFontData* fontDataForCharacter(UChar32) const override;
 
-    virtual bool isCustomFont() const override;
-    virtual bool isLoading() const override;
-    virtual bool isLoadingFallback() const override;
-    virtual bool isSegmented() const override;
-    virtual bool shouldSkipDrawing() const override;
+    bool isCustomFont() const override;
+    bool isLoading() const override;
+    bool isLoadingFallback() const override;
+    bool isSegmented() const override;
+    bool shouldSkipDrawing() const override;
 
     Vector<FontDataRange, 1> m_ranges;
 };