Create LineLayout api

Source/core/layout/line/InlineIterator.h

Index: Source/core/layout/line/InlineIterator.h
diff --git a/Source/core/layout/line/InlineIterator.h b/Source/core/layout/line/InlineIterator.h
index c1ac1669354237899a338634a85c375c7bea0e2b..20a8fa299df5d93b9e7ff347360f378f283793e3 100644
--- a/Source/core/layout/line/InlineIterator.h
+++ b/Source/core/layout/line/InlineIterator.h
@@ -27,6 +27,9 @@
 #include "core/layout/LayoutBlockFlow.h"
 #include "core/layout/LayoutInline.h"
 #include "core/layout/LayoutText.h"
+#include "core/layout/api/LineLayoutBlockFlow.h"
+#include "core/layout/api/LineLayoutInline.h"
+#include "core/layout/api/LineLayoutText.h"
 
 #include "wtf/StdLibExtras.h"
 
@@ -50,7 +53,7 @@ public:
     {
     }
 
-    InlineIterator(LayoutObject* root, LayoutObject* o, unsigned p)
+    InlineIterator(LineLayoutItem root, LineLayoutItem o, unsigned p)
         : m_root(root)
         , m_obj(o)
         , m_nextBreakablePosition(-1)
@@ -60,27 +63,27 @@ public:
 
     void clear() { moveTo(0, 0); }
 
-    void moveToStartOf(LayoutObject* object)
+    void moveToStartOf(LineLayoutItem object)
     {
         moveTo(object, 0);
     }
 
-    void moveTo(LayoutObject* object, unsigned offset, int nextBreak = -1)
+    void moveTo(LineLayoutItem object, unsigned offset, int nextBreak = -1)
     {
         m_obj = object;
         m_pos = offset;
         m_nextBreakablePosition = nextBreak;
     }
 
-    LayoutObject* object() const { return m_obj; }
-    void setObject(LayoutObject* object) { m_obj = object; }
+    LineLayoutItem object() const { return m_obj; }
+    void setObject(LineLayoutItem object) { m_obj = object; }
 
     int nextBreakablePosition() const { return m_nextBreakablePosition; }
     void setNextBreakablePosition(int position) { m_nextBreakablePosition = position; }
 
     unsigned offset() const { return m_pos; }
     void setOffset(unsigned position) { m_pos = position; }
-    LayoutObject* root() const { return m_root; }
+    LineLayoutItem root() const { return m_root; }
 
     void fastIncrementInTextNode();
     void increment(InlineBidiResolver* = nullptr, IncrementRule = FastIncrementInTextNode);
@@ -88,13 +91,13 @@ public:
 
     inline bool atTextParagraphSeparator() const
     {
-        return m_obj && m_obj->preservesNewline() && m_obj->isText() && toLayoutText(m_obj)->textLength()
-            && !toLayoutText(m_obj)->isWordBreak() && toLayoutText(m_obj)->characterAt(m_pos) == '\n';
+        return m_obj && m_obj.preservesNewline() && m_obj.isText() && LineLayoutText(m_obj).textLength()
+            && !LineLayoutText(m_obj).isWordBreak() && LineLayoutText(m_obj).characterAt(m_pos) == '\n';
     }
 
     inline bool atParagraphSeparator() const
     {
-        return (m_obj && m_obj->isBR()) || atTextParagraphSeparator();
+        return (m_obj && m_obj.isBR()) || atTextParagraphSeparator();
     }
 
     UChar characterAt(unsigned) const;
@@ -103,8 +106,8 @@ public:
     ALWAYS_INLINE WTF::Unicode::Direction direction() const;
 
 private:
-    LayoutObject* m_root;
-    LayoutObject* m_obj;
+    LineLayoutItem m_root;
+    LineLayoutItem m_obj;
 
     int m_nextBreakablePosition;
     unsigned m_pos;
@@ -129,7 +132,7 @@ static inline WTF::Unicode::Direction embedCharFromDirection(TextDirection dir,
 }
 
 template <class Observer>
-static inline void notifyObserverEnteredObject(Observer* observer, LayoutObject* object)
+static inline void notifyObserverEnteredObject(Observer* observer, LineLayoutItem object)
 {
     if (!observer || !object || !object->isLayoutInline())
         return;
@@ -156,7 +159,7 @@ static inline void notifyObserverEnteredObject(Observer* observer, LayoutObject*
 }
 
 template <class Observer>
-static inline void notifyObserverWillExitObject(Observer* observer, LayoutObject* object)
+static inline void notifyObserverWillExitObject(Observer* observer, LineLayoutItem object)
 {
     if (!observer || !object || !object->isLayoutInline())
         return;
@@ -174,7 +177,7 @@ static inline void notifyObserverWillExitObject(Observer* observer, LayoutObject
         observer->embed(WTF::Unicode::PopDirectionalFormat, FromStyleOrDOM);
 }
 
-static inline bool isIteratorTarget(LayoutObject* object)
+static inline bool isIteratorTarget(LineLayoutItem object)
 {
     ASSERT(object); // The iterator will of course return 0, but its not an expected argument to this function.
     return object->isText() || object->isFloating() || object->isOutOfFlowPositioned() || object->isReplaced();
@@ -186,15 +189,15 @@ enum EmptyInlineBehavior {
     IncludeEmptyInlines,
 };
 
-static bool isEmptyInline(LayoutObject* object)
+static bool isEmptyInline(LineLayoutItem object)
 {
     if (!object->isLayoutInline())
         return false;
 
-    for (LayoutObject* curr = toLayoutInline(object)->firstChild(); curr; curr = curr->nextSibling()) {
+    for (LineLayoutItem curr = LineLayoutInline(object).firstChild(); curr; curr = curr->nextSibling()) {
         if (curr->isFloatingOrOutOfFlowPositioned())
             continue;
-        if (curr->isText() && toLayoutText(curr)->isAllCollapsibleWhitespace())
+        if (curr->isText() && LineLayoutText(curr).isAllCollapsibleWhitespace())
             continue;
 
         if (!isEmptyInline(curr))
@@ -207,9 +210,9 @@ static bool isEmptyInline(LayoutObject* object)
 // This function will iterate over inlines within a block, optionally notifying
 // a bidi resolver as it enters/exits inlines (so it can push/pop embedding levels).
 template <class Observer>
-static inline LayoutObject* bidiNextShared(LayoutObject* root, LayoutObject* current, Observer* observer = 0, EmptyInlineBehavior emptyInlineBehavior = SkipEmptyInlines, bool* endOfInlinePtr = nullptr)
+static inline LineLayoutItem bidiNextShared(LineLayoutItem root, LineLayoutItem current, Observer* observer = 0, EmptyInlineBehavior emptyInlineBehavior = SkipEmptyInlines, bool* endOfInlinePtr = nullptr)
 {
-    LayoutObject* next = nullptr;
+    LineLayoutItem next = nullptr;
     // oldEndOfInline denotes if when we last stopped iterating if we were at the end of an inline.
     bool oldEndOfInline = endOfInlinePtr ? *endOfInlinePtr : false;
     bool endOfInline = false;
@@ -265,28 +268,28 @@ static inline LayoutObject* bidiNextShared(LayoutObject* root, LayoutObject* cur
 }
 
 template <class Observer>
-static inline LayoutObject* bidiNextSkippingEmptyInlines(LayoutObject* root, LayoutObject* current, Observer* observer)
+static inline LineLayoutItem bidiNextSkippingEmptyInlines(LineLayoutItem root, LineLayoutItem current, Observer* observer)
 {
     // The SkipEmptyInlines callers never care about endOfInlinePtr.
     return bidiNextShared(root, current, observer, SkipEmptyInlines);
 }
 
 // This makes callers cleaner as they don't have to specify a type for the observer when not providing one.
-static inline LayoutObject* bidiNextSkippingEmptyInlines(LayoutObject* root, LayoutObject* current)
+static inline LineLayoutItem bidiNextSkippingEmptyInlines(LineLayoutItem root, LineLayoutItem current)
 {
     InlineBidiResolver* observer = nullptr;
     return bidiNextSkippingEmptyInlines(root, current, observer);
 }
 
-static inline LayoutObject* bidiNextIncludingEmptyInlines(LayoutObject* root, LayoutObject* current, bool* endOfInlinePtr = nullptr)
+static inline LineLayoutItem bidiNextIncludingEmptyInlines(LineLayoutItem root, LineLayoutItem current, bool* endOfInlinePtr = nullptr)
 {
     InlineBidiResolver* observer = nullptr; // Callers who include empty inlines, never use an observer.
     return bidiNextShared(root, current, observer, IncludeEmptyInlines, endOfInlinePtr);
 }
 
-static inline LayoutObject* bidiFirstSkippingEmptyInlines(LayoutBlockFlow* root, BidiRunList<BidiRun>& runs, InlineBidiResolver* resolver = nullptr)
+static inline LineLayoutItem bidiFirstSkippingEmptyInlines(LineLayoutBlockFlow root, BidiRunList<BidiRun>& runs, InlineBidiResolver* resolver = nullptr)
 {
-    LayoutObject* o = root->firstChild();
+    LineLayoutItem o = root.firstChild();
     if (!o)
         return nullptr;
 
@@ -312,9 +315,9 @@ static inline LayoutObject* bidiFirstSkippingEmptyInlines(LayoutBlockFlow* root,
 }
 
 // FIXME: This method needs to be renamed when bidiNext finds a good name.
-static inline LayoutObject* bidiFirstIncludingEmptyInlines(LayoutBlock* root)
+static inline LineLayoutItem bidiFirstIncludingEmptyInlines(LineLayoutBlockFlow root)
 {
-    LayoutObject* o = root->firstChild();
+    LineLayoutItem o = root.firstChild();
     // If either there are no children to walk, or the first one is correct
     // then just return it.
     if (!o || o->isLayoutInline() || isIteratorTarget(o))
@@ -326,8 +329,8 @@ static inline LayoutObject* bidiFirstIncludingEmptyInlines(LayoutBlock* root)
 inline void InlineIterator::fastIncrementInTextNode()
 {
     ASSERT(m_obj);
-    ASSERT(m_obj->isText());
-    ASSERT(m_pos <= toLayoutText(m_obj)->textLength());
+    ASSERT(m_obj.isText());
+    ASSERT(m_pos <= LineLayoutText(m_obj).textLength());
     if (m_pos < INT_MAX)
         m_pos++;
 }
@@ -337,7 +340,7 @@ inline void InlineIterator::fastIncrementInTextNode()
 class InlineWalker {
 public:
     InlineWalker(LayoutBlock* root)
-        : m_root(root)
+        : m_root(LineLayoutItem(root))
         , m_current(nullptr)
         , m_atEndOfInline(false)
     {
@@ -345,21 +348,21 @@ public:
         m_current = bidiFirstIncludingEmptyInlines(m_root);
     }
 
-    LayoutBlock* root() { return m_root; }
-    LayoutObject* current() { return m_current; }
+    LineLayoutBlockFlow root() { return m_root; }
+    LineLayoutItem current() { return m_current; }
 
     bool atEndOfInline() { return m_atEndOfInline; }
     bool atEnd() const { return !m_current; }
 
-    LayoutObject* advance()
+    LineLayoutItem advance()
     {
         // FIXME: Support SkipEmptyInlines and observer parameters.
         m_current = bidiNextIncludingEmptyInlines(m_root, m_current, &m_atEndOfInline);
         return m_current;
     }
 private:
-    LayoutBlock* m_root;
-    LayoutObject* m_current;
+    LineLayoutBlockFlow m_root;
+    LineLayoutItem m_current;
     bool m_atEndOfInline;
 };
 
@@ -368,7 +371,7 @@ static inline bool endOfLineHasIsolatedObjectAncestor(const InlineIterator& isol
     if (!isolatedIterator.object() || !isIsolated(isolatedIterator.object()->style()->unicodeBidi()))
         return false;
 
-    LayoutObject* innerIsolatedObject = isolatedIterator.object();
+    LineLayoutItem innerIsolatedObject = isolatedIterator.object();
     while (innerIsolatedObject && innerIsolatedObject != isolatedIterator.root()) {
         if (innerIsolatedObject == ancestorItertor.object())
             return true;
@@ -389,9 +392,9 @@ inline void InlineIterator::increment(InlineBidiResolver* resolver, IncrementRul
         return;
     }
 
-    if (m_obj->isText()) {
+    if (m_obj.isText()) {
         fastIncrementInTextNode();
-        if (m_pos < toLayoutText(m_obj)->textLength())
+        if (m_pos < LineLayoutText(m_obj).textLength())
             return;
     }
     // bidiNext can return 0, so use moveTo instead of moveToStartOf
@@ -405,10 +408,10 @@ inline bool InlineIterator::atEnd() const
 
 inline UChar InlineIterator::characterAt(unsigned index) const
 {
-    if (!m_obj || !m_obj->isText())
+    if (!m_obj || !m_obj.isText())
         return 0;
 
-    return toLayoutText(m_obj)->characterAt(index);
+    return LineLayoutText(m_obj).characterAt(index);
 }
 
 inline UChar InlineIterator::current() const
@@ -429,8 +432,8 @@ ALWAYS_INLINE WTF::Unicode::Direction InlineIterator::direction() const
     if (UChar c = current())
         return WTF::Unicode::direction(c);
 
-    if (m_obj && m_obj->isListMarker())
-        return m_obj->style()->isLeftToRightDirection() ? WTF::Unicode::LeftToRight : WTF::Unicode::RightToLeft;
+    if (m_obj && m_obj.isListMarker())
+        return m_obj.style()->isLeftToRightDirection() ? WTF::Unicode::LeftToRight : WTF::Unicode::RightToLeft;
 
     return WTF::Unicode::OtherNeutral;
 }
@@ -480,7 +483,7 @@ template <>
 inline int InlineBidiResolver::findFirstTrailingSpaceAtRun(BidiRun* run)
 {
     ASSERT(run);
-    LayoutObject* lastObject = run->m_object;
+    LineLayoutItem lastObject = LineLayoutItem(run->m_object);
     if (!lastObject->isText())
         return run->m_stop;
 
@@ -514,16 +517,16 @@ inline bool InlineBidiResolver::needsToApplyL1Rule(BidiRunList<BidiRun>& runs)
     return true;
 }
 
-static inline bool isIsolatedInline(LayoutObject* object)
+static inline bool isIsolatedInline(LineLayoutItem object)
 {
     ASSERT(object);
     return object->isLayoutInline() && isIsolated(object->style()->unicodeBidi());
 }
 
-static inline LayoutObject* highestContainingIsolateWithinRoot(LayoutObject* object, LayoutObject* root)
+static inline LineLayoutItem highestContainingIsolateWithinRoot(LineLayoutItem object, LineLayoutItem root)
 {
     ASSERT(object);
-    LayoutObject* containingIsolateObj = 0;
+    LineLayoutItem containingIsolateObj = 0;
     while (object && object != root) {
         if (isIsolatedInline(object))
             containingIsolateObj = object;
@@ -535,7 +538,7 @@ static inline LayoutObject* highestContainingIsolateWithinRoot(LayoutObject* obj
 
 static inline unsigned numberOfIsolateAncestors(const InlineIterator& iter)
 {
-    LayoutObject* object = iter.object();
+    LineLayoutItem object = iter.object();
     if (!object)
         return 0;
     unsigned count = 0;
@@ -549,7 +552,7 @@ static inline unsigned numberOfIsolateAncestors(const InlineIterator& iter)
 
 // FIXME: This belongs on InlineBidiResolver, except it's a template specialization
 // of BidiResolver which knows nothing about LayoutObjects.
-static inline BidiRun* addPlaceholderRunForIsolatedInline(InlineBidiResolver& resolver, LayoutObject* obj, unsigned pos)
+static inline BidiRun* addPlaceholderRunForIsolatedInline(InlineBidiResolver& resolver, LineLayoutItem obj, unsigned pos)
 {
     ASSERT(obj);
     BidiRun* isolatedRun = new BidiRun(pos, pos, obj, resolver.context(), resolver.dir());
@@ -560,7 +563,7 @@ static inline BidiRun* addPlaceholderRunForIsolatedInline(InlineBidiResolver& re
     return isolatedRun;
 }
 
-static inline BidiRun* createRun(int start, int end, LayoutObject* obj, InlineBidiResolver& resolver)
+static inline BidiRun* createRun(int start, int end, LineLayoutItem obj, InlineBidiResolver& resolver)
 {
     return new BidiRun(start, end, obj, resolver.context(), resolver.dir());
 }
@@ -599,7 +602,7 @@ public:
     void commitExplicitEmbedding(BidiRunList<BidiRun>&) { }
     BidiRunList<BidiRun>& runs() { return m_runs; }
 
-    void addFakeRunIfNecessary(LayoutObject* obj, unsigned pos, unsigned end, InlineBidiResolver& resolver)
+    void addFakeRunIfNecessary(LineLayoutItem obj, unsigned pos, unsigned end, InlineBidiResolver& resolver)
     {
         // We only need to add a fake run for a given isolated span once during each call to createBidiRunsForLine.
         // We'll be called for every span inside the isolated span so we just ignore subsequent calls.
@@ -623,7 +626,7 @@ private:
     BidiRunList<BidiRun>& m_runs;
 };
 
-static void inline appendRunObjectIfNecessary(LayoutObject* obj, unsigned start, unsigned end, InlineBidiResolver& resolver, AppendRunBehavior behavior, IsolateTracker& tracker)
+static void inline appendRunObjectIfNecessary(LineLayoutItem obj, unsigned start, unsigned end, InlineBidiResolver& resolver, AppendRunBehavior behavior, IsolateTracker& tracker)
 {
     // Trailing space code creates empty BidiRun objects, start == end, so
     // that case needs to be handled specifically.
@@ -645,7 +648,7 @@ static void inline appendRunObjectIfNecessary(LayoutObject* obj, unsigned start,
     }
 }
 
-static void adjustMidpointsAndAppendRunsForObjectIfNeeded(LayoutObject* obj, unsigned start, unsigned end, InlineBidiResolver& resolver, AppendRunBehavior behavior, IsolateTracker& tracker)
+static void adjustMidpointsAndAppendRunsForObjectIfNeeded(LineLayoutItem obj, unsigned start, unsigned end, InlineBidiResolver& resolver, AppendRunBehavior behavior, IsolateTracker& tracker)
 {
     if (start > end || LayoutBlockFlow::shouldSkipCreatingRunsForObject(obj))
         return;
@@ -687,7 +690,7 @@ static void adjustMidpointsAndAppendRunsForObjectIfNeeded(LayoutObject* obj, uns
     }
 }
 
-static inline void addFakeRunIfNecessary(LayoutObject* obj, unsigned start, unsigned end, InlineBidiResolver& resolver, IsolateTracker& tracker)
+static inline void addFakeRunIfNecessary(LineLayoutItem obj, unsigned start, unsigned end, InlineBidiResolver& resolver, IsolateTracker& tracker)
 {
     tracker.setMidpointStateForRootIsolate(resolver.midpointState());
     adjustMidpointsAndAppendRunsForObjectIfNeeded(obj, start, obj->length(), resolver, AppendingFakeRun, tracker);
@@ -702,7 +705,7 @@ inline void InlineBidiResolver::appendRun(BidiRunList<BidiRun>& runs)
         // FIXME: Could this initialize from this->inIsolate() instead of walking up the layout tree?
         IsolateTracker isolateTracker(runs, numberOfIsolateAncestors(m_sor));
         int start = m_sor.offset();
-        LayoutObject* obj = m_sor.object();
+        LineLayoutItem obj = m_sor.object();
         while (obj && obj != m_eor.object() && obj != m_endOfRunAtEndOfLine.object()) {
             if (isolateTracker.inIsolate())
                 addFakeRunIfNecessary(obj, start, obj->length(), *this, isolateTracker);