Get rid of redundant layout tree update related to selection

third_party/WebKit/Source/core/editing/SelectionTemplate.h

Index: third_party/WebKit/Source/core/editing/SelectionTemplate.h
diff --git a/third_party/WebKit/Source/core/editing/SelectionTemplate.h b/third_party/WebKit/Source/core/editing/SelectionTemplate.h
index ae04d0d868cca37eca1b86650335516d362bb355..b661e9816546a66984a2716fcac12b1625907371 100644
--- a/third_party/WebKit/Source/core/editing/SelectionTemplate.h
+++ b/third_party/WebKit/Source/core/editing/SelectionTemplate.h
@@ -87,15 +87,20 @@ class CORE_EXPORT SelectionTemplate final {
   TextAffinity affinity() const { return m_affinity; }
   TextGranularity granularity() const { return m_granularity; }
   bool hasTrailingWhitespace() const { return m_hasTrailingWhitespace; }
+  bool isCaret() const { return m_base.isNotNull() && m_base == m_extent; }
   bool isDirectional() const { return m_isDirectional; }
   bool isHandleVisible() const { return m_isHandleVisible; }
   bool isNone() const { return m_base.isNull(); }
+  bool isRange() const { return m_base != m_extent; }
 
   // Returns true if |this| selection holds valid values otherwise it causes
   // assertion failure.
   bool assertValid() const;
   bool assertValidFor(const Document&) const;
 
+  const PositionTemplate<Strategy>& computeEndPosition() const;
+  const PositionTemplate<Strategy>& computeStartPosition() const;
+
   DECLARE_TRACE();
 
   void printTo(std::ostream*, const char* type) const;