Revert of Remove Mac native font type members from FontPlatformData

Source/platform/fonts/mac/MemoryActivatedFont.h

+/*
+ * Copyright (c) 2010 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef MemoryActivatedFont_h
+#define MemoryActivatedFont_h
+
+#import <wtf/RefCounted.h>
+#import <wtf/RetainPtr.h>
+#import <wtf/text/WTFString.h>
+
+typedef struct CGFont* CGFontRef;
+
+namespace blink {
+
+// MemoryActivatedFont encapsulates a font loaded from another process and
+// activated from memory.
+//
+// Responsibilities:
+// * Holder for the CGFontRef & ATSFontRef belonging to the activated font.
+// * Responsible for unloading the font container when done.
+//
+// Memory Management:
+// The class is reference counted, with each instance of FontPlatformData that
+// uses this class holding a reference to it.
+// Entries are kept track of internally in a hash to allow quick lookup
+// of existing instances for reuse:
+// - fontCacheBySrcFontContainerRef() - key is the ATSFontContainerRef
+//   corresponding to the *original in-process NSFont* whose loading was blocked
+//   by the sandbox.
+//   This is needed to allow lookup of a pre-existing MemoryActivatedFont when
+//   creating a new FontPlatformData object.
+//
+// Assumptions:
+// This code assumes that an ATSFontRef is a unique identifier tied to an
+// activated font.  i.e. After we activate a font, its ATSFontRef doesn't
+// change.
+// It also assumes that the ATSFoncontainerRef for two in-memory NSFonts that
+// correspond to the same on-disk font file are always the same and don't change
+// with time.
+//
+// Flushing caches:
+// When the system notifies us of a system font cache flush, all FontDataCache
+// objects are destroyed.  This should in turn dereference all
+// MemoryActivatedFonts and thus unload all in-memory fonts.
+class MemoryActivatedFont : public RefCounted<MemoryActivatedFont> {
+public:
+    // Use to create a new object, see docs on constructor below.
+    static PassRefPtr<MemoryActivatedFont> create(uint32_t fontID, NSFont*, CGFontRef);
+    ~MemoryActivatedFont();
+
+    // Get cached CGFontRef corresponding to the in-memory font.
+    CGFontRef cgFont() { return m_cgFont.get(); }
+
+private:
+    // srcFontRef - ATSFontRef belonging to the NSFont object that failed to
+    // load in-process.
+    // container - a font container corresponding to an identical font that
+    // we loaded cross-process.
+    MemoryActivatedFont(uint32_t fontID, NSFont*, CGFontRef);
+
+    WTF::RetainPtr<CGFontRef> m_cgFont;
+    uint32_t m_fontID;
+    WTF::String m_inSandboxHashKey;
+};
+
+} // namespace blink
+
+#endif // MemoryActivatedFont_h