Fix font-size shaking issue in some pages

third_party/WebKit/Source/core/layout/TextAutosizer.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 291 matching lines @@
       bool skip_layouted_nodes = false);
   bool ClusterWouldHaveEnoughTextToAutosize(
       const LayoutBlock* root,
       const LayoutBlock* width_provider = nullptr);
   Fingerprint GetFingerprint(LayoutObject*);
   Fingerprint ComputeFingerprint(const LayoutObject*);
   Cluster* MaybeCreateCluster(LayoutBlock*);
   float ClusterMultiplier(Cluster*);
   float SuperclusterMultiplier(Cluster*);
   // A cluster's width provider is typically the deepest block containing all
-  // text. There are exceptions, such as tables and table cells which use the
-  // table itself for width.
+  // text. There are exceptions:
+  // 1. Tables and table cells which use the table itself for width.
+  // 2. LayoutView which use itself for keeping its clusterMultiplier steady.
   const LayoutBlock* ClusterWidthProvider(const LayoutBlock*) const;
   const LayoutBlock* MaxClusterWidthProvider(
       Supercluster*,
       const LayoutBlock* current_root) const;
   // Typically this returns a block's computed width. In the case of tables
   // layout, this width is not yet known so the fixed width is used if it's
   // available, or the containing block's width otherwise.
   float WidthFromBlock(const LayoutBlock*) const;
   float MultiplierFromBlock(const LayoutBlock*);
   void ApplyMultiplier(LayoutObject*,
@@ skipping 31 matching lines @@
   FingerprintMapper fingerprint_mapper_;
   Vector<RefPtr<ComputedStyle>> styles_retained_during_layout_;
   // FIXME: All frames should share the same m_pageInfo instance.
   PageInfo page_info_;
   bool update_page_info_deferred_;
 };
 
 }  // namespace blink
 
 #endif  // TextAutosizer_h