Revert "Cherry-pick 66b364d. rdar://122130509"

This reverts commit 4e7939d.

Canonical link: https://commits.webkit.org/274941.71@safari-7619.1.5-branch

Source/WebCore/rendering/RenderInline.cpp

@@ -508,14 +508,7 @@ IntRect RenderInline::linesBoundingBox() const
 {
     if (auto* layout = LayoutIntegration::LineLayout::containing(*this)) {
         if (!layout->contains(*this))
-             return { };
-
-        if (!layoutBox()) {
-            // Repaint may be issued on subtrees during content mutation with newly inserted renderers
-            // (or we just forgot to initiate layout before querying geometry on stale content after moving inline boxes between blocks).
-            ASSERT(needsLayout());
             return { };
-        }
         return enclosingIntRect(layout->enclosingBorderBoxRectFor(*this));
     }
 
@@ -525,7 +518,6 @@ IntRect RenderInline::linesBoundingBox() const
     // unable to reproduce this at all (and consequently unable to figure ot why this is happening).  The assert will hopefully catch the problem in debug
     // builds and help us someday figure out why.  We also put in a redundant check of lastLineBox() to avoid the crash for now.
     ASSERT(!firstLineBox() == !lastLineBox());  // Either both are null or both exist.
-    IntRect result;
     if (firstLineBox() && lastLineBox()) {
         // Return the width of the minimal left side and the maximal right side.
         float logicalLeftSide = 0;