Remove support for anonymous deprecated flexboxes.

Source/core/rendering/RenderBlock.cpp

Index: Source/core/rendering/RenderBlock.cpp
diff --git a/Source/core/rendering/RenderBlock.cpp b/Source/core/rendering/RenderBlock.cpp
index 6737a7e3bdeb5f149668004ba2e4e8a1dd08c6ca..7412005e4241b42dc47891b8230cb67cf1a923d6 100644
--- a/Source/core/rendering/RenderBlock.cpp
+++ b/Source/core/rendering/RenderBlock.cpp
@@ -4899,11 +4899,7 @@ RenderBlock* RenderBlock::createAnonymousWithParentRendererAndDisplay(const Rend
     // FIXME: Do we need to convert all our inline displays to block-type in the anonymous logic ?
     EDisplay newDisplay;
     RenderBlock* newBox = 0;
-    if (display == BOX || display == INLINE_BOX) {
-        // FIXME: Remove this case once we have eliminated all internal users of old flexbox
-        newBox = RenderDeprecatedFlexibleBox::createAnonymous(&parent->document());
-        newDisplay = BOX;
-    } else if (display == FLEX || display == INLINE_FLEX) {
+    if (display == FLEX || display == INLINE_FLEX) {
         newBox = RenderFlexibleBox::createAnonymous(&parent->document());
         newDisplay = FLEX;
     } else {