[Reland] Refactor the selection code in EventHandler

Source/core/editing/SelectionController.h

Index: Source/core/editing/SelectionController.h
diff --git a/Source/core/editing/SelectionController.h b/Source/core/editing/SelectionController.h
new file mode 100644
index 0000000000000000000000000000000000000000..a8c1970b5332ad978ca20647f89ae1e5f2cd23d1
--- /dev/null
+++ b/Source/core/editing/SelectionController.h
@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2006, 2007, 2009, 2010, 2011 Apple 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:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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 SelectionController_h
+#define SelectionController_h
+
+#include "core/CoreExport.h"
+#include "core/editing/TextGranularity.h"
+#include "core/page/EventWithHitTestResults.h"
+#include "platform/heap/Handle.h"
+
+namespace blink {
+
+class FrameSelection;
+class HitTestResult;
+class LocalFrame;
+class VisibleSelection;
+
+class CORE_EXPORT SelectionController final : public NoBaseWillBeGarbageCollected<SelectionController> {
+    WTF_MAKE_NONCOPYABLE(SelectionController);
+public:
+    static PassOwnPtrWillBeRawPtr<SelectionController> create(LocalFrame*);
+    DECLARE_TRACE();
+
+    bool updateSelectionForMouseDownDispatchingSelectStart(Node*, const VisibleSelection&, TextGranularity);
+    void handleMousePressEvent(const MouseEventWithHitTestResults&);
+    bool handleMousePressEventSingleClick(const MouseEventWithHitTestResults&);
+    bool handleMousePressEventDoubleClick(const MouseEventWithHitTestResults&);
+    bool handleMousePressEventTripleClick(const MouseEventWithHitTestResults&);
+    void handleMouseDraggedEvent(const MouseEventWithHitTestResults&, const IntPoint&, const LayoutPoint&, Node*, const IntPoint&);
+    bool handleMouseReleaseEvent(const MouseEventWithHitTestResults&, const LayoutPoint&);
+    bool handlePasteGlobalSelection(const PlatformMouseEvent&);
+    bool handleGestureLongPress(const PlatformGestureEvent&, const HitTestResult&);
+
+    void updateSelectionForMouseDrag(Node*, const LayoutPoint&, const IntPoint&);
+    void updateSelectionForMouseDrag(const HitTestResult&, Node*, const LayoutPoint&, const IntPoint&);
+    void prepareForContextMenu(const MouseEventWithHitTestResults&, const LayoutPoint&);
+    void preparePassMousePressEventToSubframe(MouseEventWithHitTestResults&);
+
+    void initializeSelectionState();
+    void setMouseDownMayStartSelect(bool);
+    bool mouseDownMayStartSelect() const;
+    bool singleClickInSelection() const;
+
+private:
+    explicit SelectionController(LocalFrame*);
+
+    enum class AppendTrailingWhitespace { ShouldAppend, DontAppend };
+    void selectClosestWordFromHitTestResult(const HitTestResult&, AppendTrailingWhitespace);
+    void selectClosestMisspellingFromHitTestResult(const HitTestResult&, AppendTrailingWhitespace);
+    void selectClosestWordFromMouseEvent(const MouseEventWithHitTestResults&);
+    void selectClosestMisspellingFromMouseEvent(const MouseEventWithHitTestResults&);
+    void selectClosestWordOrLinkFromMouseEvent(const MouseEventWithHitTestResults&);
+
+    FrameSelection& selection() const;
+
+    RawPtrWillBeMember<LocalFrame> const m_frame;
+    bool m_mouseDownMayStartSelect;
+    bool m_singleClickInSelection;
+    enum class SelectionState { HaveNotStartedSelection, PlacedCaret, ExtendedSelection };
+    SelectionState m_selectionState;
+};
+
+}
+#endif // SelectionController_h