Update containtingIsolate to go back all the way to top isolate from current

Source/core/rendering/RenderBlockLineLayout.cpp

Index: Source/core/rendering/RenderBlockLineLayout.cpp
diff --git a/Source/core/rendering/RenderBlockLineLayout.cpp b/Source/core/rendering/RenderBlockLineLayout.cpp
index 5ecc8f9633d92837e3a8b41bbca34511682fe81a..e7196cfecbacc160477a00c4a8f5bd6f32a842ff 100644
--- a/Source/core/rendering/RenderBlockLineLayout.cpp
+++ b/Source/core/rendering/RenderBlockLineLayout.cpp
@@ -1317,7 +1317,8 @@ static inline void constructBidiRunsForSegment(InlineBidiResolver& topResolver,
         // tree to see which parent inline is the isolate. We could change enterIsolate
         // to take a RenderObject and do this logic there, but that would be a layering
         // violation for BidiResolver (which knows nothing about RenderObject).
-        RenderInline* isolatedInline = toRenderInline(containingIsolate(startObj, currentRoot));
+        RenderInline* isolatedInline = toRenderInline(highestContainingIsolateWithinRoot(startObj, currentRoot));
+        ASSERT(isolatedInline);
 
         InlineBidiResolver isolatedResolver;
         EUnicodeBidi unicodeBidi = isolatedInline->style()->unicodeBidi();