Add FontCache API for retrieving prioritized fallback fonts

third_party/WebKit/Source/platform/fonts/FontCache.h

 /*
  * Copyright (C) 2006, 2008 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2007-2008 Torch Mobile, Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 16 matching lines @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef FontCache_h
 #define FontCache_h
 
 #include "platform/PlatformExport.h"
 #include "platform/fonts/FallbackListCompositeKey.h"
 #include "platform/fonts/FontCacheKey.h"
 #include "platform/fonts/FontFaceCreationParams.h"
+#include "platform/fonts/FontFallbackPriority.h"
 #include "wtf/Allocator.h"
 #include "wtf/Forward.h"
 #include "wtf/HashMap.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefPtr.h"
 #include "wtf/text/CString.h"
 #include "wtf/text/Unicode.h"
 #include "wtf/text/WTFString.h"
 #include <limits.h>
 
@@ skipping 32 matching lines @@
     PassRefPtr<SimpleFontData> fallbackFontForCharacter(const FontDescription&, UChar32, const SimpleFontData* fontDataToSubstitute);
 
     // Also implemented by the platform.
     void platformInit();
 
     PassRefPtr<SimpleFontData> getFontData(const FontDescription&, const AtomicString&, bool checkingAlternateName = false, ShouldRetain = Retain);
     PassRefPtr<SimpleFontData> getLastResortFallbackFont(const FontDescription&, ShouldRetain = Retain);
     SimpleFontData* getNonRetainedLastResortFallbackFont(const FontDescription&);
     bool isPlatformFontAvailable(const FontDescription&, const AtomicString&);
 
+    const Vector<AtomicString>& fontListForFallbackPriority(const FontDescription&, FontFallbackPriority);
+
     // Returns the ShapeCache instance associated with the given cache key.
     // Creates a new instance as needed and as such is guaranteed not to return
     // a nullptr. Instances are managed by FontCache and are only guaranteed to
     // be valid for the duration of the current session, as controlled by
     // disable/enablePurging.
     ShapeCache* getShapeCache(const FallbackListCompositeKey&);
 
     void addClient(FontCacheClient*);
 #if !ENABLE(OILPAN)
     void removeClient(FontCacheClient*);
@@ skipping 66 matching lines @@
     FontPlatformData* getFontPlatformData(const FontDescription&, const FontFaceCreationParams&, bool checkingAlternateName = false);
 
     // These methods are implemented by each platform.
     PassOwnPtr<FontPlatformData> createFontPlatformData(const FontDescription&, const FontFaceCreationParams&, float fontSize);
 
     // Implemented on skia platforms.
     PassRefPtr<SkTypeface> createTypeface(const FontDescription&, const FontFaceCreationParams&, CString& name);
 
     PassRefPtr<SimpleFontData> fallbackOnStandardFontStyle(const FontDescription&, UChar32);
 
+    template <FontFallbackPriority fallbackPriority>
+    const Vector<AtomicString>& initAndGetFontListForFallbackPriority(const FontDescription&);
+
+    const Vector<AtomicString> platformFontListForFallbackPriority(FontFallbackPriority) const;
+
     // Don't purge if this count is > 0;
     int m_purgePreventCount;
 
 #if OS(WIN)
     OwnPtr<SkFontMgr> m_fontManager;
     static bool s_useDirectWrite;
     static IDWriteFactory* s_directWriteFactory;
     static float s_deviceScaleFactor;
     static bool s_useSubpixelPositioning;
     static HashMap<String, RefPtr<SkTypeface>>* s_sideloadedFonts;
@@ skipping 14 matching lines @@
     USING_FAST_MALLOC(FontCachePurgePreventer);
     WTF_MAKE_NONCOPYABLE(FontCachePurgePreventer);
 public:
     FontCachePurgePreventer() { FontCache::fontCache()->disablePurging(); }
     ~FontCachePurgePreventer() { FontCache::fontCache()->enablePurging(); }
 };
 
 } // namespace blink
 
 #endif