Added Dartium changes onto 45.0.2454.104

Source/bindings/core/dart/DartStringCache.h

-// Copyright (C) 2013 Google Inc. All rights reserved.
+// Copyright 2012, 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 GraphicsContextStateSaver_h
-#define GraphicsContextStateSaver_h
+#ifndef DartStringCache_h
+#define DartStringCache_h
 
-#include "platform/PlatformExport.h"
-#include "platform/graphics/GraphicsContext.h"
+#include "wtf/HashMap.h"
+#include "wtf/RefPtr.h"
+#include "wtf/text/StringHash.h"
+#include "wtf/text/StringImpl.h"
+
+#include <dart_api.h>
 
 namespace blink {
 
-class PLATFORM_EXPORT GraphicsContextStateSaver {
-    WTF_MAKE_FAST_ALLOCATED(GraphicsContextStateSaver);
+class DartStringCache {
 public:
-    GraphicsContextStateSaver(GraphicsContext& context, bool saveAndRestore = true)
-        : m_context(context)
-        , m_saveAndRestore(saveAndRestore)
+    DartStringCache();
+
+    Dart_WeakPersistentHandle get(StringImpl* stringImpl, bool autoDartScope = true)
     {
-        if (m_saveAndRestore)
-            m_context.save();
+        ASSERT(stringImpl);
+
+        if (m_lastStringImpl.get() == stringImpl)
+            return m_lastDartString;
+
+        return getSlow(stringImpl, autoDartScope);
     }
 
-    ~GraphicsContextStateSaver()
-    {
-        if (m_saveAndRestore)
-            m_context.restore();
-    }
+    void clearWeakHandles();
 
-    void save()
-    {
-        ASSERT(!m_saveAndRestore);
-        m_context.save();
-        m_saveAndRestore = true;
-    }
-
-    void saveIfNeeded()
-    {
-        if (saved())
-            return;
-        save();
-    }
-
-    void restore()
-    {
-        ASSERT(m_saveAndRestore);
-        m_context.restore();
-        m_saveAndRestore = false;
-    }
-
-    GraphicsContext* context() const { return &m_context; }
-    bool saved() const { return m_saveAndRestore; }
+    // FIXME: implement clearing on GC.
 
 private:
-    GraphicsContext& m_context;
-    bool m_saveAndRestore;
+    Dart_WeakPersistentHandle getSlow(StringImpl*, bool autoDartScope);
+    static void handleFinalizer(void*, Dart_WeakPersistentHandle, void* peer);
+
+    typedef HashMap<StringImpl*, Dart_WeakPersistentHandle> StringCache;
+    StringCache m_stringCache;
+    Dart_WeakPersistentHandle m_lastDartString;
+    // Note: RefPtr is a must as we cache by StringImpl* equality, not identity
+    // hence lastStringImpl might be not a key of the cache (in sense of identity)
+    // and hence it's not refed on addition.
+    RefPtr<StringImpl> m_lastStringImpl;
 };
 
-} // namespace blink
+}
 
-#endif // GraphicsContextStateSaver_h
+#endif