Revert of Move SelectionAdjust to its own file

third_party/WebKit/Source/core/editing/VisibleSelection.cpp

Index: third_party/WebKit/Source/core/editing/VisibleSelection.cpp
diff --git a/third_party/WebKit/Source/core/editing/VisibleSelection.cpp b/third_party/WebKit/Source/core/editing/VisibleSelection.cpp
index 398f5f6fea49cbb76e3da41f7f4e5dc814de8a6e..113c340ccda4173bebe19761a72a09062f70d9f1 100644
--- a/third_party/WebKit/Source/core/editing/VisibleSelection.cpp
+++ b/third_party/WebKit/Source/core/editing/VisibleSelection.cpp
@@ -30,7 +30,6 @@
 #include "core/dom/Element.h"
 #include "core/dom/Range.h"
 #include "core/editing/EditingUtilities.h"
-#include "core/editing/SelectionAdjuster.h"
 #include "core/editing/iterators/CharacterIterator.h"
 #include "core/layout/LayoutObject.h"
 #include "platform/geometry/LayoutPoint.h"
@@ -514,6 +513,56 @@
         m_affinity = TextAffinity::Downstream;
 }
 
+static Node* enclosingShadowHost(Node* node)
+{
+    for (Node* runner = node; runner; runner = ComposedTreeTraversal::parent(*runner)) {
+        if (isShadowHost(runner))
+            return runner;
+    }
+    return nullptr;
+}
+
+static bool isEnclosedBy(const PositionInComposedTree& position, const Node& node)
+{
+    ASSERT(position.isNotNull());
+    Node* anchorNode = position.anchorNode();
+    if (anchorNode == node)
+        return !position.isAfterAnchor() && !position.isBeforeAnchor();
+
+    return ComposedTreeTraversal::isDescendantOf(*anchorNode, node);
+}
+
+static bool isSelectionBoundary(const Node& node)
+{
+    return isHTMLTextAreaElement(node) || isHTMLInputElement(node) || isHTMLSelectElement(node);
+}
+
+static Node* enclosingShadowHostForStart(const PositionInComposedTree& position)
+{
+    Node* node = position.nodeAsRangeFirstNode();
+    if (!node)
+        return nullptr;
+    Node* shadowHost = enclosingShadowHost(node);
+    if (!shadowHost)
+        return nullptr;
+    if (!isEnclosedBy(position, *shadowHost))
+        return nullptr;
+    return isSelectionBoundary(*shadowHost) ? shadowHost : nullptr;
+}
+
+static Node* enclosingShadowHostForEnd(const PositionInComposedTree& position)
+{
+    Node* node = position.nodeAsRangeLastNode();
+    if (!node)
+        return nullptr;
+    Node* shadowHost = enclosingShadowHost(node);
+    if (!shadowHost)
+        return nullptr;
+    if (!isEnclosedBy(position, *shadowHost))
+        return nullptr;
+    return isSelectionBoundary(*shadowHost) ? shadowHost : nullptr;
+}
+
 template <typename Strategy>
 void VisibleSelectionTemplate<Strategy>::validate(TextGranularity granularity)
 {
@@ -594,6 +643,128 @@
         m_affinity = TextAffinity::Downstream;
     }
     didChange();
+}
+
+static PositionInComposedTree adjustPositionInComposedTreeForStart(const PositionInComposedTree& position, Node* shadowHost)
+{
+    if (isEnclosedBy(position, *shadowHost)) {
+        if (position.isBeforeChildren())
+            return PositionInComposedTree::beforeNode(shadowHost);
+        return PositionInComposedTree::afterNode(shadowHost);
+    }
+
+    // We use |firstChild|'s after instead of beforeAllChildren for backward
+    // compatibility. The positions are same but the anchors would be different,
+    // and selection painting uses anchor nodes.
+    if (Node* firstChild = ComposedTreeTraversal::firstChild(*shadowHost))
+        return PositionInComposedTree::beforeNode(firstChild);
+    return PositionInComposedTree();
+}
+
+static Position adjustPositionForEnd(const Position& currentPosition, Node* startContainerNode)
+{
+    TreeScope& treeScope = startContainerNode->treeScope();
+
+    ASSERT(currentPosition.computeContainerNode()->treeScope() != treeScope);
+
+    if (Node* ancestor = treeScope.ancestorInThisScope(currentPosition.computeContainerNode())) {
+        if (ancestor->contains(startContainerNode))
+            return positionAfterNode(ancestor);
+        return positionBeforeNode(ancestor);
+    }
+
+    if (Node* lastChild = treeScope.rootNode().lastChild())
+        return positionAfterNode(lastChild);
+
+    return Position();
+}
+
+static PositionInComposedTree adjustPositionInComposedTreeForEnd(const PositionInComposedTree& position, Node* shadowHost)
+{
+    if (isEnclosedBy(position, *shadowHost)) {
+        if (position.isAfterChildren())
+            return PositionInComposedTree::afterNode(shadowHost);
+        return PositionInComposedTree::beforeNode(shadowHost);
+    }
+
+    // We use |lastChild|'s after instead of afterAllChildren for backward
+    // compatibility. The positions are same but the anchors would be different,
+    // and selection painting uses anchor nodes.
+    if (Node* lastChild = ComposedTreeTraversal::lastChild(*shadowHost))
+        return PositionInComposedTree::afterNode(lastChild);
+    return PositionInComposedTree();
+}
+
+static Position adjustPositionForStart(const Position& currentPosition, Node* endContainerNode)
+{
+    TreeScope& treeScope = endContainerNode->treeScope();
+
+    ASSERT(currentPosition.computeContainerNode()->treeScope() != treeScope);
+
+    if (Node* ancestor = treeScope.ancestorInThisScope(currentPosition.computeContainerNode())) {
+        if (ancestor->contains(endContainerNode))
+            return positionBeforeNode(ancestor);
+        return positionAfterNode(ancestor);
+    }
+
+    if (Node* firstChild = treeScope.rootNode().firstChild())
+        return positionBeforeNode(firstChild);
+
+    return Position();
+}
+
+// TODO(yosin): We should move
+// |SelectionAdjuster::adjustSelectionToAvoidCrossingShadowBoundaries()| to
+// "SelectionAdjuster.cpp"
+void SelectionAdjuster::adjustSelectionToAvoidCrossingShadowBoundaries(VisibleSelection* selection)
+{
+    // Note: |m_selectionType| isn't computed yet.
+    ASSERT(selection->base().isNotNull());
+    ASSERT(selection->extent().isNotNull());
+    ASSERT(selection->start().isNotNull());
+    ASSERT(selection->end().isNotNull());
+
+    // TODO(hajimehoshi): Checking treeScope is wrong when a node is
+    // distributed, but we leave it as it is for backward compatibility.
+    if (selection->start().anchorNode()->treeScope() == selection->end().anchorNode()->treeScope())
+        return;
+
+    if (selection->isBaseFirst()) {
+        const Position& newEnd = adjustPositionForEnd(selection->end(), selection->start().computeContainerNode());
+        selection->m_extent = newEnd;
+        selection->m_end = newEnd;
+        return;
+    }
+
+    const Position& newStart = adjustPositionForStart(selection->start(), selection->end().computeContainerNode());
+    selection->m_extent = newStart;
+    selection->m_start = newStart;
+}
+
+// TODO(yosin): We should move
+// |SelectionAdjuster::adjustSelectionToAvoidCrossingShadowBoundaries()| to
+// "SelectionAdjuster.cpp"
+// This function is called twice. The first is called when |m_start| and |m_end|
+// or |m_extent| are same, and the second when |m_start| and |m_end| are changed
+// after downstream/upstream.
+void SelectionAdjuster::adjustSelectionToAvoidCrossingShadowBoundaries(VisibleSelectionInComposedTree* selection)
+{
+    Node* const shadowHostStart = enclosingShadowHostForStart(selection->start());
+    Node* const shadowHostEnd = enclosingShadowHostForEnd(selection->end());
+    if (shadowHostStart == shadowHostEnd)
+        return;
+
+    if (selection->isBaseFirst()) {
+        Node* const shadowHost = shadowHostStart ? shadowHostStart : shadowHostEnd;
+        const PositionInComposedTree& newEnd = adjustPositionInComposedTreeForEnd(selection->end(), shadowHost);
+        selection->m_extent = newEnd;
+        selection->m_end = newEnd;
+        return;
+    }
+    Node* const shadowHost = shadowHostEnd ? shadowHostEnd : shadowHostStart;
+    const PositionInComposedTree& newStart = adjustPositionInComposedTreeForStart(selection->start(), shadowHost);
+    selection->m_extent = newStart;
+    selection->m_start = newStart;
 }
 
 template <typename Strategy>