Autosize flex boxes.

Source/core/rendering/RenderDeprecatedFlexibleBox.cpp

Index: Source/core/rendering/RenderDeprecatedFlexibleBox.cpp
diff --git a/Source/core/rendering/RenderDeprecatedFlexibleBox.cpp b/Source/core/rendering/RenderDeprecatedFlexibleBox.cpp
index babcd3ddae8c8f98202dc71a46c5fa86daec60a1..5a3dd907c0f066ae0241241360c52f11a73ae144 100644
--- a/Source/core/rendering/RenderDeprecatedFlexibleBox.cpp
+++ b/Source/core/rendering/RenderDeprecatedFlexibleBox.cpp
@@ -26,6 +26,7 @@
 #include "core/rendering/RenderDeprecatedFlexibleBox.h"
 
 #include "core/frame/UseCounter.h"
+#include "core/rendering/FastTextAutosizer.h"
 #include "core/rendering/LayoutRepainter.h"
 #include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderView.h"
@@ -270,6 +271,8 @@ void RenderDeprecatedFlexibleBox::layoutBlock(bool relayoutChildren)
         updateLogicalWidth();
         updateLogicalHeight();
 
+        FastTextAutosizer::LayoutScope fastTextAutosizerLayoutScope(this);
+
         if (previousSize != size()
             || (parent()->isDeprecatedFlexibleBox() && parent()->style()->boxOrient() == HORIZONTAL
             && parent()->style()->boxAlign() == BSTRETCH))