Moving GraphicsContext and dependencies from core to platform.

Source/core/platform/mac/LocalCurrentGraphicsContext.h

-/*
- * Copyright (C) 2006 Apple Computer, Inc.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public License
- * along with this library; see the file COPYING.LIB.  If not, write to
- * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
- * Boston, MA 02110-1301, USA.
- */
-
-#include "core/platform/graphics/GraphicsContext.h"
-#include "wtf/Noncopyable.h"
-
-#include "skia/ext/skia_utils_mac.h"
-
-OBJC_CLASS NSGraphicsContext;
-
-namespace WebCore {
-
-// This class automatically saves and restores the current NSGraphicsContext for
-// functions which call out into AppKit and rely on the currentContext being set
-class LocalCurrentGraphicsContext {
-    WTF_MAKE_NONCOPYABLE(LocalCurrentGraphicsContext);
-public:
-    LocalCurrentGraphicsContext(GraphicsContext* graphicsContext);
-    ~LocalCurrentGraphicsContext();
-    CGContextRef cgContext();
-private:
-    GraphicsContext* m_savedGraphicsContext;
-    NSGraphicsContext* m_savedNSGraphicsContext;
-    bool m_didSetGraphicsContext;
-    gfx::SkiaBitLocker m_skiaBitLocker;
-};
-
-class ContextContainer {
-    WTF_MAKE_NONCOPYABLE(ContextContainer);
-public:
-    ContextContainer(GraphicsContext*);
-
-    // This synchronizes the CGContext to reflect the current SkCanvas state.
-    // The implementation may not return the same CGContext each time.
-    CGContextRef context() { return m_skiaBitLocker.cgContext(); }
-
-private:
-    gfx::SkiaBitLocker m_skiaBitLocker;
-};
-
-}